1<?xml version="1.0" encoding="iso-8859-1"?> 2<!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc"> 3<chapter id="secure"> 4 <title>Secure Office Networking</title> 5 6 <para> 7 Congratulations, your Samba networking skills are developing nicely. You started out 8 with three simple networks in <link linkend="simple"/>, and then in <link linkend="small"/> 9 you designed and built a network that provides a high degree of flexibility, integrity, 10 and dependability. It was enough for the basic needs each was designed to fulfill. In 11 this chapter you address a more complex set of needs. The solution you explore 12 introduces you to basic features that are specific to Samba-3. 13 </para> 14 15 <para> 16 You should note that a working and secure solution could be implemented using Samba-2.2.x. 17 In the exercises presented here, you are gradually using more Samba-3-specific features, 18 so caution is advised for anyone who tries to use Samba-2.2.x with the guidance here given. 19 To avoid confusion, this book is all about Samba-3. Let's get the exercises in this 20 chapter underway. 21 </para> 22 23<sect1> 24 <title>Introduction</title> 25 26 <para> 27 You have made Mr. Meany a very happy man. Recently he paid you a fat bonus for work 28 well done. It is one year since the last network upgrade. You have been quite busy. 29 Two months ago Mr. Meany gave approval to hire Christine Roberson, who has taken over 30 general network management. Soon she will provide primary user support. You have 31 demonstrated that you can delegate responsibility and can plan and execute according 32 to that plan. Above all, you have shown Mr. Meany that you are a responsible person. 33 Today is a big day. Mr. Meany called you to his office at 9 a.m. for news you never 34 expected: You are going to take charge of business operations. Mr. Meany 35 is retiring and has entrusted the business to your capable hands. 36 </para> 37 38 <para> 39 Mr. Meany may be retiring from this company, but not from work. He is taking the 40 opportunity to develop Abmas Accounting into a larger and more substantial company. 41 He says that it took him many years to learn that there is no future in just running 42 a business. He now realizes there is great personal satisfaction in the creation of 43 career opportunities for people in the local community. He wants to do more for others, 44 as he is doing for you. Today he spent a lot of time talking about his grand plan 45 for growth, which you will deal with in the chapters ahead. 46 </para> 47 48 <para> 49 Over the past year, the growth projections were exceeded. The network has grown to 50 meet the needs of 130 users. Along with growth, the demand for improved services 51 and better functionality has also developed. You are about to make an interim 52 improvement and then hand over all Help desk and network maintenance to Christine. 53 Christine has professional certifications in Microsoft Windows as well as in Linux; 54 she is a hard worker and quite likable. Christine does not want to manage the department 55 (although she manages well). She gains job satisfaction when left to sort things out. 56 Occasionally she wants to work with you on a challenging problem. When you told her 57 about your move, she almost resigned, although she was reassured that a new manager would 58 be hired to run Information Technology, and she would be responsible only for operations. 59 </para> 60 61 <sect2> 62 <title>Assignment Tasks</title> 63 64 <para> 65 You promised the staff Internet services including Web browsing, electronic mail, virus 66 protection, and a company Web site. Christine is eager to help turn the vision into 67 reality. Let's see how close you can get to the promises made. 68 </para> 69 70 <para> 71 The network you are about to deliver will service 130 users today. Within a year, 72 Abmas will aquire another company. Mr. Meany claims that within 2 years there will be 73 well over 500 users on the network. You have bought into the big picture, so prepare 74 for growth. You have purchased a new server and will implement a new network infrastructure. 75 </para> 76 77 <para> 78 You have decided to not recycle old network components. The only items that will be 79 carried forward are notebook computers. You offered staff new notebooks, but not 80 one person wanted the disruption for what was perceived as a marginal update. 81 You decided to give everyone, even the notebook user, a new desktop computer. 82 </para> 83 84 <para> 85 You procured a DSL Internet connection that provides 1.5 Mb/sec (bidirectional) 86 and a 10 Mb/sec ethernet port. You registered the domain 87 <constant>abmas.us</constant>, and the Internet Service Provider (ISP) is supplying 88 secondary DNS. Information furnished by your ISP is shown in <link linkend="chap4netid"/>. 89 </para> 90 91 <para> 92 It is of paramount priority that under no circumstances will Samba offer 93 service access from an Internet connection. You are paying an ISP to 94 give, as part of its value-added services, full firewall protection for your 95 connection to the outside world. The only services allowed in from 96 the Internet side are the following destination ports: <constant>http/https (ports 97 80 and 443), email (port 25), DNS (port 53)</constant>. All Internet traffic 98 will be allowed out after network address translation (NAT). No internal IP addresses 99 are permitted through the NAT filter because complete privacy of internal network 100 operations must be assured. 101 </para> 102 103 <table id="chap4netid"> 104 <title>Abmas.US ISP Information</title> 105 <tgroup cols="2"> 106 <colspec align="left"/> 107 <colspec align="center"/> 108 <thead> 109 <row> 110 <entry>Parameter</entry> 111 <entry>Value</entry> 112 </row> 113 </thead> 114 <tbody> 115 <row> 116 <entry>Server IP Address</entry> 117 <entry>123.45.67.66</entry> 118 </row> 119 <row> 120 <entry>DSL Device IP Address</entry> 121 <entry>123.45.67.65</entry> 122 </row> 123 <row> 124 <entry>Network Address</entry> 125 <entry>123.45.67.64/30</entry> 126 </row> 127 <row> 128 <entry>Gateway Address</entry> 129 <entry>123.45.54.65</entry> 130 </row> 131 <row> 132 <entry>Primary DNS Server</entry> 133 <entry>123.45.54.65</entry> 134 </row> 135 <row> 136 <entry>Secondary DNS Server</entry> 137 <entry>123.45.54.32</entry> 138 </row> 139 <row> 140 <entry>Forwarding DNS Server</entry> 141 <entry>123.45.12.23</entry> 142 </row> 143 </tbody> 144 </tgroup> 145 </table> 146 147 <figure id="ch04net"> 148 <title>Abmas Network Topology &smbmdash; 130 Users</title> 149 <imagefile scale="65">chap4-net</imagefile> 150 </figure> 151 152 <para> 153 Christine recommended that desktop systems should be installed from a single cloned 154 master system that has a minimum of locally installed software and loads all software 155 off a central application server. The benefit of having the central application server 156 is that it allows single-point maintenance of all business applications, a more 157 efficient way to manage software. She further recommended installation of antivirus 158 software on workstations as well as on the Samba server. Christine knows the dangers 159 of potential virus infection and insists on a comprehensive approach to detective 160 as well as corrective action to protect network operations. 161 </para> 162 163 <para> 164 A significant concern is the problem of managing company growth. Recently, a number 165 of users had to share a PC while waiting for new machines to arrive. This presented 166 some problems with desktop computers and software installation into the new users' 167 desktop profiles. 168 </para> 169 170 </sect2> 171</sect1> 172 173<sect1> 174 <title>Dissection and Discussion</title> 175 176 <para> 177 Many of the conclusions you draw here are obvious. Some requirements are not very clear 178 or may simply be your means of drawing the most out of Samba-3. Much can be done more simply 179 than you will demonstrate here, but keep in mind that the network must scale to at least 500 180 users. This means that some functionality will be overdesigned for the current 130-user 181 environment. 182 </para> 183 184 <sect2> 185 <title>Technical Issues</title> 186 187 <para> 188 In this exercise we use a 24-bit subnet mask for the two local networks. This, 189 of course, limits our network to a maximum of 253 usable IP addresses. The network 190 address range chosen is one assigned by RFC1918 for private networks. 191 When the number of users on the network begins to approach the limit of usable 192 addresses, it is a good idea to switch to a network address specified in RFC1918 193 in the 172.16.0.0/16 range. This is done in subsequent chapters. 194 </para> 195 196 <para> 197 <indexterm><primary>tdbsam</primary></indexterm> 198 <indexterm><primary>smbpasswd</primary></indexterm> 199 The high growth rates projected are a good reason to use the <constant>tdbsam</constant> 200 passdb backend. The use of <constant>smbpasswd</constant> for the backend may result in 201 performance problems. The <constant>tdbsam</constant> passdb backend offers features that 202 are not available with the older, flat ASCII-based <constant>smbpasswd</constant> database. 203 </para> 204 205 <para> 206 <indexterm><primary>risk</primary></indexterm> 207 The proposed network design uses a single server to act as an Internet services host for 208 electronic mail, Web serving, remote administrative access via SSH, 209 Samba-based file and print services. This design is often chosen by sites that feel 210 they cannot afford or justify the cost or overhead of having separate servers. It must 211 be realized that if security of this type of server should ever be violated (compromised), 212 the whole network and all data is at risk. Many sites continue to choose this type 213 of solution; therefore, this chapter provides detailed coverage of key implementation 214 aspects. 215 </para> 216 217 <para> 218 Samba will be configured to specifically not operate on the Ethernet interface that is 219 directly connected to the Internet. 220 </para> 221 222 <para> 223 <indexterm><primary>iptables</primary></indexterm> 224 <indexterm><primary>NAT</primary></indexterm> 225 <indexterm><primary>Network Address Translation</primary><see>NAT</see></indexterm> 226 <indexterm><primary>firewall</primary></indexterm> 227 You know that your ISP is providing full firewall services, but you cannot rely on that. 228 Always assume that human error will occur, so be prepared by using Linux firewall facilities 229 based on <command>iptables</command> to effect NAT. Block all 230 incoming traffic except to permitted well-known ports. You must also allow incoming packets 231 to establish outgoing connections. You will permit all internal outgoing requests. 232 </para> 233 234 <para> 235 The configuration of Web serving, Web proxy services, electronic mail, and the details of 236 generic antivirus handling are beyond the scope of this book and therefore are not 237 covered except insofar as this affects Samba-3. 238 </para> 239 240 <para> 241 <indexterm><primary>login</primary></indexterm> 242 Notebook computers are configured to use a network login when in the office and a 243 local account to log in while away from the office. Users store all work done in 244 transit (away from the office) by using a local share for work files. Standard procedures 245 dictate that on completion of the work that necessitates mobile file access, all 246 work files are moved back to secure storage on the office server. Staff is instructed 247 to not carry on any company notebook computer any files that are not absolutely required. 248 This is a preventative measure to protect client information as well as private business 249 records. 250 </para> 251 252 <para> 253 <indexterm><primary>application server</primary></indexterm> 254 All applications are served from the central server from a share called <constant>apps</constant>. 255 Microsoft Office XP Professional and OpenOffice 1.1.0 will be installed using a network 256 (or administrative) installation. Accounting and financial management software can also 257 be run only from the central application server. Notebook users are provided with 258 locally installed applications on a need-to-have basis only. 259 </para> 260 261 <para> 262 <indexterm><primary>roaming profiles</primary></indexterm> 263 The introduction of roaming profiles support means that users can move between 264 desktop computer systems without constraint while retaining full access to their data. 265 The desktop travels with them as they move. 266 </para> 267 268 <para> 269 <indexterm><primary>DNS</primary></indexterm> 270 The DNS server implementation must now address both internal and external 271 needs. You forward DNS lookups to your ISP-provided server as well as the 272 <constant>abmas.us</constant> external secondary DNS server. 273 </para> 274 275 <para> 276 <indexterm><primary>dynamic DNS</primary></indexterm> 277 <indexterm><primary>DDNS</primary><see>dynamic DNS</see></indexterm> 278 <indexterm><primary>DHCP server</primary></indexterm> 279 Compared with the DHCP server configuration in <link linkend="small"/>, <link linkend="dhcp01"/>, the 280 configuration used in this example has to deal with the presence of an Internet connection. 281 The scope set for it ensures that no DHCP services will be offered on the external 282 connection. All printers are configured as DHCP clients so that the DHCP server assigns 283 the printer a fixed IP address by way of the Ethernet interface (MAC) address. One additional 284 feature of this DHCP server configuration file is the inclusion of parameters to allow dynamic 285 DNS (DDNS) operation. 286 </para> 287 288 <para> 289 This is the first implementation that depends on a correctly functioning DNS server. 290 Comprehensive steps are included to provide for a fully functioning DNS server that also 291 is enabled for DDNS operation. This means that DHCP clients can be autoregistered 292 with the DNS server. 293 </para> 294 295 <para> 296 You are taking the opportunity to manually set the netbios name of the Samba server to 297 a name other than what will be automatically resolved. You are doing this to ensure that 298 the machine has the same NetBIOS name on both network segments. 299 </para> 300 301 <para> 302 As in the previous network configuration, printing in this network configuration uses 303 direct raw printing (i.e., no smart printing and no print driver autodownload to Windows 304 clients). Printer drivers are installed on the Windows client manually. This is not 305 a problem because Christine is to install and configure one single workstation and 306 then clone that configuration, using Norton Ghost, to all workstations. Each machine is 307 identical, so this should pose no problem. 308 </para> 309 310 <sect3> 311 <title>Hardware Requirements</title> 312 313 <para> 314 <indexterm><primary>memory requirements</primary></indexterm> 315 This server runs a considerable number of services. From similarly configured Linux 316 installations, the approximate calculated memory requirements are as shown in 317 <link linkend="ch4memoryest"/>. 318 319<example id="ch4memoryest"> 320<title>Estimation of Memory Requirements</title> 321<screen> 322Application Memory per User 130 Users 500 Users 323 Name (MBytes) Total MBytes Total MBytes 324----------- --------------- ------------ ------------ 325DHCP 2.5 3 3 326DNS 16.0 16 16 327Samba (nmbd) 16.0 16 16 328Samba (winbind) 16.0 16 16 329Samba (smbd) 4.0 520 2000 330Apache 10.0 (20 User) 200 200 331CUPS 3.5 16 32 332Basic OS 256.0 256 256 333 -------------- -------------- 334 Total: 1043 MBytes 2539 MBytes 335 -------------- -------------- 336</screen> 337</example> 338 You should add a safety margin of at least 50% to these estimates. The minimum 339 system memory recommended for initial startup 1 GB, but to permit the system 340 to scale to 500 users, it makes sense to provision the machine with 4 GB memory. 341 An initial configuration with only 1 GB memory would lead to early performance complaints 342 as the system load builds up. Given the low cost of memory, it does not make sense to 343 compromise in this area. 344 </para> 345 346 <para> 347 <indexterm><primary>bandwidth calculations</primary></indexterm> 348 Aggregate input/output loads should be considered for sizing network configuration as 349 well as disk subsystems. For network bandwidth calculations, one would typically use an 350 estimate of 0.1 MB/sec per user. This suggests that 100-Base-T (approx. 10 MB/sec) 351 would deliver below acceptable capacity for the initial user load. It is therefore a good 352 idea to begin with 1 Gb Ethernet cards for the two internal networks, each attached 353 to a 1 Gb Ethernet switch that provides connectivity to an expandable array of 100-Base-T 354 switched ports. 355 </para> 356 357 <para> 358 <indexterm><primary>network segments</primary></indexterm> 359 <indexterm><primary>RAID</primary></indexterm> 360 Considering the choice of 1 Gb Ethernet interfaces for the two local network segments, 361 the aggregate network I/O capacity will be 2100 Mb/sec (about 230 MB/sec), an I/O 362 demand that would require a fast disk storage I/O capability. Peak disk throughput is 363 limited by the disk subsystem chosen. It is desirable to provide the maximum 364 I/O bandwidth affordable. If a low-cost solution must be chosen, 365 3Ware IDE RAID Controllers are a good choice. These controllers can be fitted into a 366 64-bit, 66 MHz PCI-X slot. They appear to the operating system as a high-speed SCSI 367 controller that can operate at the peak of the PCI-X bandwidth (approximately 450 MB/sec). 368 Alternative SCSI-based hardware RAID controllers should also be considered. Alternately, 369 it makes sense to purchase well-known, branded hardware that has appropriate performance 370 specifications. As a minimum, one should attempt to provide a disk subsystem that can 371 deliver I/O rates of at least 100 MB/sec. 372 </para> 373 374 <para> 375 Disk storage requirements may be calculated as shown in <link linkend="ch4diskest"/>. 376 377<example id="ch4diskest"> 378<title>Estimation of Disk Storage Requirements</title> 379<screen> 380Corporate Data: 100 MBytes/user per year 381Email Storage: 500 MBytes/user per year 382Applications: 5000 MBytes 383Safety Buffer: At least 50% 384 385Given 500 Users and 2 years: 386----------------------------- 387 Corporate Data: 2 x 100 x 500 = 100000 MBytes = 100 GBytes 388 Email Storage: 2 x 500 x 500 = 500000 MBytes = 500 GBytes 389 Applications: 5000 MBytes = 5 GBytes 390 ---------------------------- 391 Total: 605 GBytes 392 Add 50% buffer 303 GBytes 393 Recommended Storage: 908 GBytes 394</screen> 395</example> 396 <indexterm><primary>storage capacity</primary></indexterm> 397 The preferred storage capacity should be approximately 1 Terabyte. Use of RAID level 5 398 with two hot spare drives would require an 8-drive by 200 GB capacity per drive array. 399 </para> 400 401 </sect3> 402 403 </sect2> 404 405 406 <sect2> 407 <title>Political Issues</title> 408 409 <para> 410 Your industry is coming under increasing accountability pressures. Increased paranoia 411 is necessary so you can demonstrate that you have acted with due diligence. You must 412 not trust your Internet connection. 413 </para> 414 415 <para> 416 Apart from permitting more efficient management of business applications through use of 417 an application server, your primary reason for the decision to implement this is that it 418 gives you greater control over software licensing. 419 </para> 420 421 <para> 422 <indexterm><primary>Outlook Express</primary></indexterm> 423 You are well aware that the current configuration results in some performance issues 424 as the size of the desktop profile grows. Given that users use Microsoft Outlook 425 Express, you know that the storage implications of the <constant>.PST</constant> file 426 is something that needs to be addressed later. 427 </para> 428 429 </sect2> 430 431</sect1> 432 433<sect1> 434 <title>Implementation</title> 435 436 <para> 437 <link linkend="ch04net"/> demonstrates the overall design of the network that you will implement. 438 </para> 439 440 <para> 441 The information presented here assumes that you are already familiar with many basic steps. 442 As this stands, the details provided already extend well beyond just the necessities of 443 Samba configuration. This decision is deliberate to ensure that key determinants 444 of a successful installation are not overlooked. This is the last case that documents 445 the finite minutiae of DHCP and DNS server configuration. Beyond the information provided 446 here, there are many other good reference books on these subjects. 447 </para> 448 449 <para> 450 The &smb.conf; file has the following noteworthy features: 451 </para> 452 453 <itemizedlist> 454 <listitem><para> 455 The NetBIOS name of the Samba server is set to <constant>DIAMOND</constant>. 456 </para></listitem> 457 458 <listitem><para> 459 The Domain name is set to <constant>PROMISES</constant>. 460 </para></listitem> 461 462 <listitem><para> 463 <indexterm><primary>broadcast messages</primary></indexterm> 464 <indexterm><primary>interfaces</primary></indexterm> 465 <indexterm><primary>bind interfaces only</primary></indexterm> 466 Ethernet interface <constant>eth0</constant> is attached to the Internet connection 467 and is externally exposed. This interface is explicitly not available for Samba to use. 468 Samba listens on this interface for broadcast messages but does not broadcast any 469 information on <constant>eth0</constant>, nor does it accept any connections from it. 470 This is achieved by way of the <parameter>interfaces</parameter> parameter and the 471 <parameter>bind interfaces only</parameter> entry. 472 </para></listitem> 473 474 <listitem><para> 475 <indexterm><primary>passdb backend</primary></indexterm> 476 <indexterm><primary>tdbsam</primary></indexterm> 477 <indexterm><primary>binary database</primary></indexterm> 478 The <parameter>passdb backend</parameter> parameter specifies the creation and use 479 of the <constant>tdbsam</constant> password backend. This is a binary database that 480 has excellent scalability for a large number of user account entries. 481 </para></listitem> 482 483 <listitem><para> 484 <indexterm><primary>WINS serving</primary></indexterm> 485 <indexterm><primary>wins support</primary></indexterm> 486 <indexterm><primary>name resolve order</primary></indexterm> 487 WINS serving is enabled by the <smbconfoption name="wins support">Yes</smbconfoption>, 488 and name resolution is set to use it by means of the 489 <smbconfoption name="name resolve order">wins bcast hosts</smbconfoption> entry. 490 </para></listitem> 491 492 <listitem><para> 493 <indexterm><primary>time server</primary></indexterm> 494 The Samba server is configured for use by Windows clients as a time server. 495 </para></listitem> 496 497 <listitem><para> 498 <indexterm><primary>CUPS</primary></indexterm> 499 <indexterm><primary>printing</primary></indexterm> 500 <indexterm><primary>printcap name</primary></indexterm> 501 Samba is configured to directly interface with CUPS via the direct internal interface 502 that is provided by CUPS libraries. This is achieved with the 503 <smbconfoption name="printing">CUPS</smbconfoption> as well as the 504 <smbconfoption name="printcap name">CUPS</smbconfoption> entries. 505 </para></listitem> 506 507 <listitem><para> 508 <indexterm><primary>user management</primary></indexterm> 509 <indexterm><primary>group management</primary></indexterm> 510 <indexterm><primary>SRVTOOLS.EXE</primary></indexterm> 511 External interface scripts are provided to enable Samba to interface smoothly to 512 essential operating system functions for user and group management. This is important 513 to enable workstations to join the Domain and is also important so that you can use 514 the Windows NT4 Domain User Manager as well as the Domain Server Manager. These tools 515 are provided as part of the <filename>SRVTOOLS.EXE</filename> toolkit that can be 516 downloaded from the Microsoft FTP 517 <ulink url="ftp://ftp.microsoft.com/Softlib/MSLFILES/SRVTOOLS.EXE">site</ulink>. 518 </para></listitem> 519 520 <listitem><para> 521 <indexterm><primary>User Mode</primary></indexterm> 522 The &smb.conf; file specifies that the Samba server will operate in (default) <parameter> 523 security = user</parameter> mode<footnote><para>See <emphasis>TOSHARG2</emphasis>, Chapter 3. 524 This is necessary so that Samba can act as a Domain Controller (PDC); see 525 <emphasis>TOSHARG2</emphasis>, Chapter 4, for additional information.</para></footnote> 526 (User Mode). 527 </para></listitem> 528 529 <listitem><para> 530 <indexterm><primary>logon services</primary></indexterm> 531 <indexterm><primary>logon script</primary></indexterm> 532 Domain logon services as well as a Domain logon script are specified. The logon script 533 will be used to add robustness to the overall network configuration. 534 </para></listitem> 535 536 <listitem><para> 537 <indexterm><primary>roaming profiles</primary></indexterm> 538 <indexterm><primary>logon path</primary></indexterm> 539 <indexterm><primary>profile share</primary></indexterm> 540 Roaming profiles are enabled through the specification of the parameter, 541 <smbconfoption name="logon path">\\%L\profiles\%U</smbconfoption>. The value of this parameter translates the 542 <constant>%L</constant> to the name by which the Samba server is called by the client (for this 543 configuration, it translates to the name <constant>DIAMOND</constant>), and the <constant>%U</constant> 544 will translate to the name of the user within the context of the connection made to the profile share. 545 It is the administrator's responsibility to ensure there is a directory in the root of the 546 profile share for each user. This directory must be owned by the user also. An exception to this 547 requirement is when a profile is created for group use. 548 </para></listitem> 549 550 <listitem><para> 551 <indexterm><primary>virus</primary></indexterm> 552 <indexterm><primary>opportunistic locking</primary></indexterm> 553 Precautionary veto is effected for particular Windows file names that have been targeted by 554 virus-related activity. Additionally, Microsoft Office files are vetoed from opportunistic locking 555 controls. This should help to prevent lock contention-related file access problems. 556 </para></listitem> 557 558 <listitem><para> 559 Every user has a private home directory on the UNIX/Linux host. This is mapped to 560 a network drive that is the same for all users. 561 </para></listitem> 562 563 </itemizedlist> 564 565 <para> 566 The configuration of the server is the most complex so far. The following steps are used: 567 </para> 568 569 <orderedlist numeration="arabic"> 570 <listitem><para> 571 Basic System Configuration 572 </para></listitem> 573 574 <listitem><para> 575 Samba Configuration 576 </para></listitem> 577 578 <listitem><para> 579 DHCP and DNS Server Configuration 580 </para></listitem> 581 582 <listitem><para> 583 Printer Configuration 584 </para></listitem> 585 586 <listitem><para> 587 Process Start-up Configuration 588 </para></listitem> 589 590 <listitem><para> 591 Validation 592 </para></listitem> 593 594 <listitem><para> 595 Application Share Configuration 596 </para></listitem> 597 598 <listitem><para> 599 Windows Client Configuration 600 </para></listitem> 601 </orderedlist> 602 603 <para> 604 The following sections cover each step in logical and defined detail. 605 </para> 606 607 <sect2 id="ch4bsc"> 608 <title>Basic System Configuration</title> 609 610 <para> 611 <indexterm><primary>SUSE Enterprise Linux Server</primary></indexterm> 612 The preparation in this section assumes that your SUSE Enterprise Linux Server 8.0 system has been 613 freshly installed. It prepares basic files so that the system is ready for comprehensive 614 operation in line with the network diagram shown in <link linkend="ch04net"/>. 615 </para> 616 617 <procedure> 618 <title>Server Configuration Steps</title> 619 620 <step><para> 621 <indexterm><primary>hostname</primary></indexterm> 622 Using the UNIX/Linux system tools, name the server <constant>server.abmas.us</constant>. 623 Verify that your hostname is correctly set by running: 624<screen> 625&rootprompt; uname -n 626server 627</screen> 628 An alternate method to verify the hostname is: 629<screen> 630&rootprompt; hostname -f 631server.abmas.us 632</screen> 633 </para></step> 634 635 <step><para> 636 <indexterm><primary>/etc/hosts</primary></indexterm> 637 <indexterm><primary>localhost</primary></indexterm> 638 Edit your <filename>/etc/hosts</filename> file to include the primary names and addresses 639 of all network interfaces that are on the host server. This is necessary so that during 640 startup the system can resolve all its own names to the IP address prior to 641 startup of the DNS server. An example of entries that should be in the 642 <filename>/etc/hosts</filename> file is: 643<screen> 644127.0.0.1 localhost 645192.168.1.1 sleeth1.abmas.biz sleeth1 diamond 646192.168.2.1 sleeth2.abmas.biz sleeth2 647123.45.67.66 server.abmas.us server 648</screen> 649 You should check the startup order of your system. If the CUPS print server is started before 650 the DNS server (<command>named</command>), you should also include an entry for the printers 651 in the <filename>/etc/hosts</filename> file, as follows: 652<screen> 653192.168.1.20 qmsa.abmas.biz qmsa 654192.168.1.30 hplj6a.abmas.biz hplj6a 655192.168.2.20 qmsf.abmas.biz qmsf 656192.168.2.30 hplj6f.abmas.biz hplj6f 657</screen> 658 <indexterm><primary>named</primary></indexterm> 659 <indexterm><primary>cupsd</primary></indexterm> 660 <indexterm><primary>daemon</primary></indexterm> 661 The printer entries are not necessary if <command>named</command> is started prior to 662 startup of <command>cupsd</command>, the CUPS daemon. 663 </para></step> 664 665 <step><para> 666 <indexterm><primary>/etc/rc.d/boot.local</primary></indexterm> 667 <indexterm><primary>IP forwarding</primary></indexterm> 668 <indexterm><primary>/proc/sys/net/ipv4/ip_forward</primary></indexterm> 669 The host server is acting as a router between the two internal network segments as well 670 as for all Internet access. This necessitates that IP forwarding be enabled. This can be 671 achieved by adding to the <filename>/etc/rc.d/boot.local</filename> an entry as follows: 672<screen> 673echo 1 > /proc/sys/net/ipv4/ip_forward 674</screen> 675 To ensure that your kernel is capable of IP forwarding during configuration, you may 676 wish to execute that command manually also. This setting permits the Linux system to 677 act as a router.<footnote><para>You may want to do the echo command last and include 678 "0" in the init scripts, since it opens up your network for a short time.</para></footnote> 679 </para></step> 680 681 <step><para> 682 <indexterm><primary>firewall</primary></indexterm> 683 <indexterm><primary>abmas-netfw.sh</primary></indexterm> 684 Installation of a basic firewall and NAT facility is necessary. 685 The following script can be installed in the <filename>/usr/local/sbin</filename> 686 directory. It is executed from the <filename>/etc/rc.d/boot.local</filename> startup 687 script. In your case, this script is called <filename>abmas-netfw.sh</filename>. The 688 script contents are shown in <link linkend="ch4natfw"/>. 689 690<example id="ch4natfw"> 691<title>NAT Firewall Configuration Script</title> 692<screen> 693#!/bin/sh 694echo -e "\n\nLoading NAT firewall.\n" 695IPTABLES=/usr/sbin/iptables 696EXTIF="eth0" 697INTIFA="eth1" 698INTIFB="eth2" 699 700/sbin/depmod -a 701/sbin/modprobe ip_tables 702/sbin/modprobe ip_conntrack 703/sbin/modprobe ip_conntrack_ftp 704/sbin/modprobe iptable_nat 705/sbin/modprobe ip_nat_ftp 706$IPTABLES -P INPUT DROP 707$IPTABLES -F INPUT 708$IPTABLES -P OUTPUT ACCEPT 709$IPTABLES -F OUTPUT 710$IPTABLES -P FORWARD DROP 711$IPTABLES -F FORWARD 712 713$IPTABLES -A INPUT -i lo -j ACCEPT 714$IPTABLES -A INPUT -i $INTIFA -j ACCEPT 715$IPTABLES -A INPUT -i $INTIFB -j ACCEPT 716$IPTABLES -A INPUT -i $EXTIF -m state --state ESTABLISHED,RELATED -j ACCEPT 717# Enable incoming traffic for: SSH, SMTP, DNS(tcp), HTTP, HTTPS 718for i in 22 25 53 80 443 719do 720 $IPTABLES -A INPUT -i $EXTIF -p tcp --dport $i -j ACCEPT 721done 722# Allow DNS(udp) 723$IPTABLES -A INPUT -i $EXTIF -p udp -dport 53 -j ACCEPT 724echo "Allow all connections OUT and only existing and specified ones IN" 725$IPTABLES -A FORWARD -i $EXTIF -o $INTIFA -m state \ 726 --state ESTABLISHED,RELATED -j ACCEPT 727$IPTABLES -A FORWARD -i $EXTIF -o $INTIFB -m state \ 728 --state ESTABLISHED,RELATED -j ACCEPT 729$IPTABLES -A FORWARD -i $INTIFA -o $EXTIF -j ACCEPT 730$IPTABLES -A FORWARD -i $INTIFB -o $EXTIF -j ACCEPT 731$IPTABLES -A FORWARD -j LOG 732echo " Enabling SNAT (MASQUERADE) functionality on $EXTIF" 733$IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE 734echo "1" > /proc/sys/net/ipv4/ip_forward 735echo -e "\nNAT firewall done.\n" 736</screen> 737</example> 738 </para></step> 739 740 <step><para> 741 Execute the following to make the script executable: 742<screen> 743&rootprompt; chmod 755 /usr/local/sbin/abmas-natfw.sh 744</screen> 745 You must now edit <filename>/etc/rc.d/boot.local</filename> to add an entry 746 that runs your <command>abmas-natfw.sh</command> script. The following 747 entry works for you: 748<screen> 749#! /bin/sh 750# 751# Copyright (c) 2002 SUSE Linux AG Nuernberg, Germany. 752# All rights reserved. 753# 754# Author: Werner Fink, 1996 755# Burchard Steinbild, 1996 756# 757# /etc/init.d/boot.local 758# 759# script with local commands to be executed from init on system startup 760# 761# Here you should add things that should happen directly after booting 762# before we're going to the first run level. 763# 764/usr/local/sbin/abmas-natfw.sh 765</screen> 766 </para></step> 767 </procedure> 768 769 <para> 770 <indexterm><primary>/etc/hosts</primary></indexterm> 771 The server is now ready for Samba configuration. During the validation step, you remove 772 the entry for the Samba server <constant>diamond</constant> from the <filename>/etc/hosts</filename> 773 file. This is done after you are satisfied that DNS-based name resolution is functioning correctly. 774 </para> 775 776 </sect2> 777 778 <sect2> 779 <title>Samba Configuration</title> 780 781 <para> 782 When you have completed this section, the Samba server is ready for testing and validation; 783 however, testing and validation have to wait until DHCP, DNS, and printing (CUPS) services have 784 been configured. 785 </para> 786 787 <procedure> 788 <title>Samba Configuration Steps</title> 789 790 <step><para> 791 Install the Samba-3 binary RPM from the Samba-Team FTP site. Assuming that the binary 792 RPM file is called <filename>samba-3.0.20-1.i386.rpm</filename>, one way to install this 793 file is as follows: 794<screen> 795&rootprompt; rpm -Uvh samba-3.0.20-1.i386.rpm 796</screen> 797 This operation must be performed while logged in as the <command>root</command> user. 798 Successful operation is clearly indicated. If this installation should fail for any reason, 799 refer to the operating system manufacturer's documentation for guidance. 800 </para></step> 801 802 <step><para> 803 Install the &smb.conf; file shown in <link linkend="promisnet"/>, <link linkend="promisnetsvca"/>, 804 and <link linkend="promisnetsvcb"/>. Concatenate (join) all three files to make a single &smb.conf; 805 file. The final, fully qualified path for this file should be <filename>/etc/samba/smb.conf</filename>. 806 807<example id="promisnet"> 808<title>130 User Network with <emphasis>tdbsam</emphasis> &smbmdash; [globals] Section</title> 809<smbconfblock> 810<smbconfcomment>Global parameters</smbconfcomment> 811<smbconfsection name="[global]"/> 812<smbconfoption name="workgroup">PROMISES</smbconfoption> 813<smbconfoption name="netbios name">DIAMOND</smbconfoption> 814<smbconfoption name="interfaces">eth1, eth2, lo</smbconfoption> 815<smbconfoption name="bind interfaces only">Yes</smbconfoption> 816<smbconfoption name="passdb backend">tdbsam</smbconfoption> 817<smbconfoption name="pam password change">Yes</smbconfoption> 818<smbconfoption name="passwd program">/usr/bin/passwd %u</smbconfoption> 819<smbconfoption name="passwd chat">*New*Password* %n\n *Re-enter*new*password*%n\n *Password*changed*</smbconfoption> 820<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption> 821<smbconfoption name="unix password sync">Yes</smbconfoption> 822<smbconfoption name="log level">1</smbconfoption> 823<smbconfoption name="syslog">0</smbconfoption> 824<smbconfoption name="log file">/var/log/samba/%m</smbconfoption> 825<smbconfoption name="max log size">50</smbconfoption> 826<smbconfoption name="smb ports">139</smbconfoption> 827<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption> 828<smbconfoption name="time server">Yes</smbconfoption> 829<smbconfoption name="printcap name">CUPS</smbconfoption> 830<smbconfoption name="show add printer wizard">No</smbconfoption> 831<smbconfoption name="add user script">/usr/sbin/useradd -m '%u'</smbconfoption> 832<smbconfoption name="delete user script">/usr/sbin/userdel -r '%u'</smbconfoption> 833<smbconfoption name="add group script">/usr/sbin/groupadd '%g'</smbconfoption> 834<smbconfoption name="delete group script">/usr/sbin/groupdel '%g'</smbconfoption> 835<smbconfoption name="add user to group script">/usr/sbin/usermod -G '%g' '%u'</smbconfoption> 836<smbconfoption name="add machine script">/usr/sbin/useradd -s /bin/false -d /tmp '%u'</smbconfoption> 837<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption> 838<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption> 839<smbconfoption name="logon script">scripts\logon.bat</smbconfoption> 840<smbconfoption name="logon path">\\%L\profiles\%U</smbconfoption> 841<smbconfoption name="logon drive">X:</smbconfoption> 842<smbconfoption name="logon home">\\%L\%U</smbconfoption> 843<smbconfoption name="domain logons">Yes</smbconfoption> 844<smbconfoption name="preferred master">Yes</smbconfoption> 845<smbconfoption name="wins support">Yes</smbconfoption> 846<smbconfoption name="utmp">Yes</smbconfoption> 847<smbconfoption name="map acl inherit">Yes</smbconfoption> 848<smbconfoption name="printing">cups</smbconfoption> 849<smbconfoption name="cups options">Raw</smbconfoption> 850<smbconfoption name="veto files">/*.eml/*.nws/*.{*}/</smbconfoption> 851<smbconfoption name="veto oplock files">/*.doc/*.xls/*.mdb/</smbconfoption> 852</smbconfblock> 853</example> 854 855<example id="promisnetsvca"> 856<title>130 User Network with <emphasis>tdbsam</emphasis> &smbmdash; Services Section Part A</title> 857<smbconfblock> 858<smbconfsection name="[homes]"/> 859<smbconfoption name="comment">Home Directories</smbconfoption> 860<smbconfoption name="valid users">%S</smbconfoption> 861<smbconfoption name="read only">No</smbconfoption> 862<smbconfoption name="browseable">No</smbconfoption> 863 864<smbconfsection name="[printers]"/> 865<smbconfoption name="comment">SMB Print Spool</smbconfoption> 866<smbconfoption name="path">/var/spool/samba</smbconfoption> 867<smbconfoption name="guest ok">Yes</smbconfoption> 868<smbconfoption name="printable">Yes</smbconfoption> 869<smbconfoption name="use client driver">Yes</smbconfoption> 870<smbconfoption name="default devmode">Yes</smbconfoption> 871<smbconfoption name="browseable">No</smbconfoption> 872 873<smbconfsection name="[netlogon]"/> 874<smbconfoption name="comment">Network Logon Service</smbconfoption> 875<smbconfoption name="path">/var/lib/samba/netlogon</smbconfoption> 876<smbconfoption name="guest ok">Yes</smbconfoption> 877<smbconfoption name="locking">No</smbconfoption> 878 879<smbconfsection name="[profiles]"/> 880<smbconfoption name="comment">Profile Share</smbconfoption> 881<smbconfoption name="path">/var/lib/samba/profiles</smbconfoption> 882<smbconfoption name="read only">No</smbconfoption> 883<smbconfoption name="profile acls">Yes</smbconfoption> 884 885<smbconfsection name="[accounts]"/> 886<smbconfoption name="comment">Accounting Files</smbconfoption> 887<smbconfoption name="path">/data/accounts</smbconfoption> 888<smbconfoption name="read only">No</smbconfoption> 889</smbconfblock> 890</example> 891 892<example id="promisnetsvcb"> 893<title>130 User Network with <emphasis>tdbsam</emphasis> &smbmdash; Services Section Part B</title> 894<smbconfblock> 895<smbconfsection name="[service]"/> 896<smbconfoption name="comment">Financial Services Files</smbconfoption> 897<smbconfoption name="path">/data/service</smbconfoption> 898<smbconfoption name="read only">No</smbconfoption> 899 900<smbconfsection name="[pidata]"/> 901<smbconfoption name="comment">Property Insurance Files</smbconfoption> 902<smbconfoption name="path">/data/pidata</smbconfoption> 903<smbconfoption name="read only">No</smbconfoption> 904 905<smbconfsection name="[apps]"/> 906<smbconfoption name="comment">Application Files</smbconfoption> 907<smbconfoption name="path">/apps</smbconfoption> 908<smbconfoption name="read only">Yes</smbconfoption> 909<smbconfoption name="admin users">bjordan</smbconfoption> 910</smbconfblock> 911</example> 912 </para></step> 913 914 <step><para> 915 <indexterm><primary>administrator</primary></indexterm><indexterm> 916 <primary>smbpasswd</primary> 917 </indexterm> 918 Add the <constant>root</constant> user to the password backend as follows: 919<screen> 920&rootprompt; smbpasswd -a root 921New SMB password: XXXXXXXX 922Retype new SMB password: XXXXXXXX 923&rootprompt; 924</screen> 925 The <constant>root</constant> account is the UNIX equivalent of the Windows Domain Administrator. 926 This account is essential in the regular maintenance of your Samba server. It must never be 927 deleted. If for any reason the account is deleted, you may not be able to recreate this account 928 without considerable trouble. 929 </para></step> 930 931 <step><para> 932 <indexterm><primary>username map</primary></indexterm> 933 Create the username map file to permit the <constant>root</constant> account to be called 934 <constant>Administrator</constant> from the Windows network environment. To do this, create 935 the file <filename>/etc/samba/smbusers</filename> with the following contents: 936<screen> 937#### 938# User mapping file 939#### 940# File Format 941# ----------- 942# Unix_ID = Windows_ID 943# 944# Examples: 945# root = Administrator 946# janes = "Jane Smith" 947# jimbo = Jim Bones 948# 949# Note: If the name contains a space it must be double quoted. 950# In the example above the name 'jimbo' will be mapped to Windows 951# user names 'Jim' and 'Bones' because the space was not quoted. 952####################################################################### 953root = Administrator 954#### 955# End of File 956#### 957</screen> 958 </para></step> 959 960 <step><para> 961 <indexterm><primary>initGrps.sh</primary></indexterm> 962 <indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>add</tertiary></indexterm> 963 <indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>modify</tertiary></indexterm> 964 <indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>list</tertiary></indexterm> 965 Create and map Windows Domain Groups to UNIX groups. A sample script is provided in <link linkend="small"/>, 966 <link linkend="initGrps"/>. Create a file containing this script. We called ours 967 <filename>/etc/samba/initGrps.sh</filename>. Set this file so it can be executed, 968 and then execute the script. Sample output should be as follows: 969 970<example id="ch4initGrps"> 971<title>Script to Map Windows NT Groups to UNIX Groups</title> 972<indexterm><primary>initGrps.sh</primary></indexterm> 973<screen> 974#!/bin/bash 975# 976# initGrps.sh 977# 978 979# Create UNIX groups 980groupadd acctsdep 981groupadd finsrvcs 982 983# Map Windows Domain Groups to UNIX groups 984net groupmap add ntgroup="Domain Admins" unixgroup=root type=d 985net groupmap add ntgroup="Domain Users" unixgroup=users type=d 986net groupmap add ntgroup="Domain Guests" unixgroup=nobody type=d 987 988# Add Functional Domain Groups 989net groupmap add ntgroup="Accounts Dept" unixgroup=acctsdep type=d 990net groupmap add ntgroup="Financial Services" unixgroup=finsrvcs type=d 991net groupmap add ntgroup="Insurance Group" unixgroup=piops type=d 992 993# Map Windows NT machine local groups to local UNIX groups 994# Mapping of local groups is not necessary and not functional 995# for this installation. 996</screen> 997</example> 998 999<screen> 1000&rootprompt; chmod 755 initGrps.sh 1001&rootprompt; /etc/samba # ./initGrps.sh 1002Updated mapping entry for Domain Admins 1003Updated mapping entry for Domain Users 1004Updated mapping entry for Domain Guests 1005No rid or sid specified, choosing algorithmic mapping 1006Successfully added group Accounts Dept to the mapping db 1007No rid or sid specified, choosing algorithmic mapping 1008Successfully added group Domain Guests to the mapping db 1009 1010&rootprompt; /etc/samba # net groupmap list | sort 1011Account Operators (S-1-5-32-548) -> -1 1012Accounts Dept (S-1-5-21-179504-2437109-488451-2003) -> acctsdep 1013Administrators (S-1-5-32-544) -> -1 1014Backup Operators (S-1-5-32-551) -> -1 1015Domain Admins (S-1-5-21-179504-2437109-488451-512) -> root 1016Domain Guests (S-1-5-21-179504-2437109-488451-514) -> nobody 1017Domain Users (S-1-5-21-179504-2437109-488451-513) -> users 1018Financial Services (S-1-5-21-179504-2437109-488451-2005) -> finsrvcs 1019Guests (S-1-5-32-546) -> -1 1020Power Users (S-1-5-32-547) -> -1 1021Print Operators (S-1-5-32-550) -> -1 1022Replicators (S-1-5-32-552) -> -1 1023System Operators (S-1-5-32-549) -> -1 1024Users (S-1-5-32-545) -> -1 1025</screen> 1026 </para></step> 1027 1028 <step><para> 1029 <indexterm><primary>useradd</primary></indexterm> 1030 <indexterm><primary>adduser</primary></indexterm> 1031 <indexterm><primary>passwd</primary></indexterm> 1032 <indexterm><primary>smbpasswd</primary></indexterm> 1033 <indexterm><primary>/etc/passwd</primary></indexterm> 1034 <indexterm><primary>password</primary><secondary>backend</secondary></indexterm> 1035 <indexterm><primary>user</primary><secondary>management</secondary></indexterm> 1036 There is one preparatory step without which you will not have a working Samba 1037 network environment. You must add an account for each network user. 1038 For each user who needs to be given a Windows Domain account, make an entry in the 1039 <filename>/etc/passwd</filename> file as well as in the Samba password backend. 1040 Use the system tool of your choice to create the UNIX system account, and use the Samba 1041 <command>smbpasswd</command> to create a Domain user account. 1042 There are a number of tools for user management under UNIX, such as 1043 <command>useradd</command>, and <command>adduser</command>, as well as a plethora of custom 1044 tools. You also want to create a home directory for each user. 1045 You can do this by executing the following steps for each user: 1046<screen> 1047&rootprompt; useradd -m <parameter>username</parameter> 1048&rootprompt; passwd <parameter>username</parameter> 1049Changing password for <parameter>username</parameter>. 1050New password: XXXXXXXX 1051Re-enter new password: XXXXXXXX 1052Password changed 1053&rootprompt; smbpasswd -a <parameter>username</parameter> 1054New SMB password: XXXXXXXX 1055Retype new SMB password: XXXXXXXX 1056Added user <parameter>username</parameter>. 1057</screen> 1058 You do of course use a valid user login ID in place of <parameter>username</parameter>. 1059 </para></step> 1060 1061 <step><para> 1062 <indexterm><primary>file system</primary><secondary>access control</secondary></indexterm> 1063 <indexterm><primary>file system</primary><secondary>permissions</secondary></indexterm> 1064 <indexterm><primary>group membership</primary></indexterm> 1065 Using the preferred tool for your UNIX system, add each user to the UNIX groups created 1066 previously as necessary. File system access control will be based on UNIX group membership. 1067 </para></step> 1068 1069 <step><para> 1070 Create the directory mount point for the disk subsystem that can be mounted to provide 1071 data storage for company files. In this case the mount point is indicated in the &smb.conf; 1072 file is <filename>/data</filename>. Format the file system as required, and mount the formatted 1073 file system partition using appropriate system tools. 1074 </para></step> 1075 1076 <step><para> 1077 <indexterm><primary>file system</primary><secondary>permissions</secondary></indexterm> 1078 Create the top-level file storage directories for data and applications as follows: 1079<screen> 1080&rootprompt; mkdir -p /data/{accounts,finsrvcs} 1081&rootprompt; mkdir -p /apps 1082&rootprompt; chown -R root:root /data 1083&rootprompt; chown -R root:root /apps 1084&rootprompt; chown -R bjordan:acctsdep /data/accounts 1085&rootprompt; chown -R bjordan:finsrvcs /data/finsrvcs 1086&rootprompt; chmod -R ug+rwxs,o-rwx /data 1087&rootprompt; chmod -R ug+rwx,o+rx-w /apps 1088</screen> 1089 Each department is responsible for creating its own directory structure within the departmental 1090 share. The directory root of the <command>accounts</command> share is <filename>/data/accounts</filename>. 1091 The directory root of the <command>finsvcs</command> share is <filename>/data/finsvcs</filename>. 1092 The <filename>/apps</filename> directory is the root of the <constant>apps</constant> share 1093 that provides the application server infrastructure. 1094 </para></step> 1095 1096 <step><para> 1097 The &smb.conf; file specifies an infrastructure to support roaming profiles and network 1098 logon services. You can now create the file system infrastructure to provide the 1099 locations on disk that these services require. Adequate planning is essential, 1100 since desktop profiles can grow to be quite large. For planning purposes, a minimum of 1101 200 MB of storage should be allowed per user for profile storage. The following 1102 commands create the directory infrastructure needed: 1103<screen> 1104&rootprompt; mkdir -p /var/spool/samba 1105&rootprompt; mkdir -p /var/lib/samba/{netlogon/scripts,profiles} 1106&rootprompt; chown -R root:root /var/spool/samba 1107&rootprompt; chown -R root:root /var/lib/samba 1108&rootprompt; chmod a+rwxt /var/spool/samba 1109&rootprompt; chmod 2775 /var/lib/samba/profiles 1110&rootprompt; chgrp users /var/lib/samba/profiles 1111</screen> 1112 For each user account that is created on the system, the following commands should be 1113 executed: 1114<screen> 1115&rootprompt; mkdir /var/lib/samba/profiles/'username' 1116&rootprompt; chown 'username':users /var/lib/samba/profiles/'username' 1117&rootprompt; chmod ug+wrx,o+rx,-w /var/lib/samba/profiles/'username' 1118</screen> 1119 </para></step> 1120 1121 <step><para> 1122 <indexterm><primary>logon scrip</primary></indexterm> 1123 <indexterm><primary>unix2dos</primary></indexterm> 1124 <indexterm><primary>dos2unix</primary></indexterm> 1125 Create a logon script. It is important that each line is correctly terminated with 1126 a carriage return and line-feed combination (i.e., DOS encoding). The following procedure 1127 works if the right tools (<constant>unix2dos</constant> and <constant>dos2unix</constant>) are installed. 1128 First, create a file called <filename>/var/lib/samba/netlogon/scripts/logon.bat.unix</filename> 1129 with the following contents: 1130<screen> 1131net time \\diamond /set /yes 1132net use h: /home 1133net use p: \\diamond\apps 1134</screen> 1135 Convert the UNIX file to a DOS file using the <command>unix2dos</command> as shown here: 1136<screen> 1137&rootprompt; unix2dos < /var/lib/samba/netlogon/scripts/logon.bat.unix \ 1138 > /var/lib/samba/netlogon/scripts/logon.bat 1139</screen> 1140 </para></step> 1141 </procedure> 1142 1143 </sect2> 1144 1145 <sect2 id="ch4dhcpdns"> 1146 <title>Configuration of DHCP and DNS Servers</title> 1147 1148 <para> 1149 DHCP services are a basic component of the entire network client installation. DNS operation is 1150 foundational to Internet access as well as to trouble-free operation of local networking. When 1151 you have completed this section, the server should be ready for solid duty operation. 1152 </para> 1153 1154 <procedure> 1155 <title>DHCP and DNS Server Configuration Steps</title> 1156 1157 <step><para> 1158 <indexterm><primary>/etc/dhcpd.conf</primary></indexterm> 1159 Create a file called <filename>/etc/dhcpd.conf</filename> with the contents as 1160 shown in <link linkend="prom-dhcp"/>. 1161 1162<example id="prom-dhcp"> 1163<title>DHCP Server Configuration File &smbmdash; <filename>/etc/dhcpd.conf</filename></title> 1164<screen> 1165# Abmas Accounting Inc. 1166default-lease-time 86400; 1167max-lease-time 172800; 1168default-lease-time 86400; 1169option ntp-servers 192.168.1.1; 1170option domain-name "abmas.biz"; 1171option domain-name-servers 192.168.1.1, 192.168.2.1; 1172option netbios-name-servers 192.168.1.1, 192.168.2.1; 1173option netbios-node-type 8; ### Node type = Hybrid ### 1174ddns-updates on; ### Dynamic DNS enabled ### 1175ddns-update-style interim; 1176 1177subnet 192.168.1.0 netmask 255.255.255.0 { 1178 range dynamic-bootp 192.168.1.128 192.168.1.254; 1179 option subnet-mask 255.255.255.0; 1180 option routers 192.168.1.1; 1181 allow unknown-clients; 1182 host qmsa { 1183 hardware ethernet 08:00:46:7a:35:e4; 1184 fixed-address 192.168.1.20; 1185 } 1186 host hplj6a { 1187 hardware ethernet 00:03:47:cb:81:e0; 1188 fixed-address 192.168.1.30; 1189 } 1190 } 1191subnet 192.168.2.0 netmask 255.255.255.0 { 1192 range dynamic-bootp 192.168.2.128 192.168.2.254; 1193 option subnet-mask 255.255.255.0; 1194 option routers 192.168.2.1; 1195 allow unknown-clients; 1196 host qmsf { 1197 hardware ethernet 01:04:31:db:e1:c0; 1198 fixed-address 192.168.1.20; 1199 } 1200 host hplj6f { 1201 hardware ethernet 00:03:47:cf:83:e2; 1202 fixed-address 192.168.2.30; 1203 } 1204 } 1205subnet 127.0.0.0 netmask 255.0.0.0 { 1206 } 1207subnet 123.45.67.64 netmask 255.255.255.252 { 1208 } 1209</screen> 1210</example> 1211 </para></step> 1212 1213 <step><para> 1214 <indexterm><primary>/etc/named.conf</primary></indexterm> 1215 Create a file called <filename>/etc/named.conf</filename> that has the combined contents 1216 of the <link linkend="ch4namedcfg"/>, <link linkend="ch4namedvarfwd"/>, and 1217 <link linkend="ch4namedvarrev"/> files that are concatenated (merged) in this 1218 specific order. 1219 </para></step> 1220 1221 <step><para> 1222 Create the files shown in their respective directories as shown in <link linkend="namedrscfiles">DNS 1223 (named) Resource Files</link>. 1224 1225 <table id="namedrscfiles"> 1226 <title>DNS (named) Resource Files</title> 1227 <tgroup cols="2"> 1228 <colspec align="left"/> 1229 <colspec align="left"/> 1230 <thead> 1231 <row> 1232 <entry>Reference</entry> 1233 <entry>File Location</entry> 1234 </row> 1235 </thead> 1236 <tbody> 1237 <row> 1238 <entry><link linkend="loopback"/></entry> 1239 <entry>/var/lib/named/localhost.zone</entry> 1240 </row> 1241 <row> 1242 <entry><link linkend="dnsloopy"/></entry> 1243 <entry>/var/lib/named/127.0.0.zone</entry> 1244 </row> 1245 <row> 1246 <entry><link linkend="roothint"/></entry> 1247 <entry>/var/lib/named/root.hint</entry> 1248 </row> 1249 <row> 1250 <entry><link linkend="abmasbiz"/></entry> 1251 <entry>/var/lib/named/master/abmas.biz.hosts</entry> 1252 </row> 1253 <row> 1254 <entry><link linkend="abmasus"/></entry> 1255 <entry>/var/lib/named/abmas.us.hosts</entry> 1256 </row> 1257 <row> 1258 <entry><link linkend="eth1zone"/></entry> 1259 <entry>/var/lib/named/192.168.1.0.rev</entry> 1260 </row> 1261 <row> 1262 <entry><link linkend="eth2zone"/></entry> 1263 <entry>/var/lib/named/192.168.2.0.rev</entry> 1264 </row> 1265 </tbody> 1266 </tgroup> 1267 </table> 1268 1269<example id="ch4namedcfg"> 1270<title>DNS Master Configuration File &smbmdash; <filename>/etc/named.conf</filename> Master Section</title> 1271<indexterm><primary>/etc/named.conf</primary></indexterm> 1272<screen> 1273### 1274# Abmas Biz DNS Control File 1275### 1276# Date: November 15, 2003 1277### 1278options { 1279 directory "/var/lib/named"; 1280 forwarders { 1281 123.45.12.23; 1282 }; 1283 forward first; 1284 listen-on { 1285 mynet; 1286 }; 1287 auth-nxdomain yes; 1288 multiple-cnames yes; 1289 notify no; 1290}; 1291 1292zone "." in { 1293 type hint; 1294 file "root.hint"; 1295}; 1296 1297zone "localhost" in { 1298 type master; 1299 file "localhost.zone"; 1300}; 1301 1302zone "0.0.127.in-addr.arpa" in { 1303 type master; 1304 file "127.0.0.zone"; 1305}; 1306 1307acl mynet { 1308 192.168.1.0/24; 1309 192.168.2.0/24; 1310 127.0.0.1; 1311}; 1312 1313acl seconddns { 1314 123.45.54.32; 1315}; 1316 1317</screen> 1318</example> 1319 1320<example id="ch4namedvarfwd"> 1321<title>DNS Master Configuration File &smbmdash; <filename>/etc/named.conf</filename> Forward Lookup Definition Section</title> 1322<screen> 1323zone "abmas.biz" { 1324 type master; 1325 file "/var/lib/named/master/abmas.biz.hosts"; 1326 allow-query { 1327 mynet; 1328 }; 1329 allow-transfer { 1330 mynet; 1331 }; 1332 allow-update { 1333 mynet; 1334 }; 1335}; 1336 1337zone "abmas.us" { 1338 type master; 1339 file "/var/lib/named/master/abmas.us.hosts"; 1340 allow-query { 1341 any; 1342 }; 1343 allow-transfer { 1344 seconddns; 1345 }; 1346}; 1347</screen> 1348</example> 1349 1350<example id="ch4namedvarrev"> 1351<title>DNS Master Configuration File &smbmdash; <filename>/etc/named.conf</filename> Reverse Lookup Definition Section</title> 1352<screen> 1353zone "1.168.192.in-addr.arpa" { 1354 type master; 1355 file "/var/lib/named/master/192.168.1.0.rev"; 1356 allow-query { 1357 mynet; 1358 }; 1359 allow-transfer { 1360 mynet; 1361 }; 1362 allow-update { 1363 mynet; 1364 }; 1365}; 1366 1367zone "2.168.192.in-addr.arpa" { 1368 type master; 1369 file "/var/lib/named/master/192.168.2.0.rev"; 1370 allow-query { 1371 mynet; 1372 }; 1373 allow-transfer { 1374 mynet; 1375 }; 1376 allow-update { 1377 mynet; 1378 }; 1379}; 1380</screen> 1381</example> 1382 1383<example id="eth1zone"> 1384<title>DNS 192.168.1 Reverse Zone File</title> 1385<screen> 1386$ORIGIN . 1387$TTL 38400 ; 10 hours 40 minutes 13881.168.192.in-addr.arpa IN SOA sleeth.abmas.biz. root.abmas.biz. ( 1389 2003021825 ; serial 1390 10800 ; refresh (3 hours) 1391 3600 ; retry (1 hour) 1392 604800 ; expire (1 week) 1393 38400 ; minimum (10 hours 40 minutes) 1394 ) 1395 NS sleeth1.abmas.biz. 1396$ORIGIN 1.168.192.in-addr.arpa. 13971 PTR sleeth1.abmas.biz. 139820 PTR qmsa.abmas.biz. 139930 PTR hplj6a.abmas.biz. 1400</screen> 1401</example> 1402 1403<example id="eth2zone"> 1404<title>DNS 192.168.2 Reverse Zone File</title> 1405<screen> 1406$ORIGIN . 1407$TTL 38400 ; 10 hours 40 minutes 14082.168.192.in-addr.arpa IN SOA sleeth.abmas.biz. root.abmas.biz. ( 1409 2003021825 ; serial 1410 10800 ; refresh (3 hours) 1411 3600 ; retry (1 hour) 1412 604800 ; expire (1 week) 1413 38400 ; minimum (10 hours 40 minutes) 1414 ) 1415 NS sleeth2.abmas.biz. 1416$ORIGIN 2.168.192.in-addr.arpa. 14171 PTR sleeth2.abmas.biz. 141820 PTR qmsf.abmas.biz. 141930 PTR hplj6f.abmas.biz. 1420</screen> 1421</example> 1422 1423<example id="abmasbiz"> 1424<title>DNS Abmas.biz Forward Zone File</title> 1425<screen> 1426$ORIGIN . 1427$TTL 38400 ; 10 hours 40 minutes 1428abmas.biz IN SOA sleeth1.abmas.biz. root.abmas.biz. ( 1429 2003021833 ; serial 1430 10800 ; refresh (3 hours) 1431 3600 ; retry (1 hour) 1432 604800 ; expire (1 week) 1433 38400 ; minimum (10 hours 40 minutes) 1434 ) 1435 NS dns.abmas.biz. 1436 MX 10 mail.abmas.biz. 1437$ORIGIN abmas.biz. 1438sleeth1 A 192.168.1.1 1439sleeth2 A 192.168.2.1 1440qmsa A 192.168.1.20 1441hplj6a A 192.168.1.30 1442qmsf A 192.168.2.20 1443hplj6f A 192.168.2.30 1444dns CNAME sleeth1 1445diamond CNAME sleeth1 1446mail CNAME sleeth1 1447</screen> 1448</example> 1449 1450<example id="abmasus"> 1451<title>DNS Abmas.us Forward Zone File</title> 1452<screen> 1453$ORIGIN . 1454$TTL 38400 ; 10 hours 40 minutes 1455abmas.us IN SOA server.abmas.us. root.abmas.us. ( 1456 2003021833 ; serial 1457 10800 ; refresh (3 hours) 1458 3600 ; retry (1 hour) 1459 604800 ; expire (1 week) 1460 38400 ; minimum (10 hours 40 minutes) 1461 ) 1462 NS dns.abmas.us. 1463 NS dns2.abmas.us. 1464 MX 10 mail.abmas.us. 1465$ORIGIN abmas.us. 1466server A 123.45.67.66 1467dns2 A 123.45.54.32 1468gw A 123.45.67.65 1469www CNAME server 1470mail CNAME server 1471dns CNAME server 1472</screen> 1473</example> 1474 1475 </para></step> 1476 1477 <step><para> 1478 <indexterm><primary>/etc/resolv.conf</primary></indexterm><indexterm> 1479 <primary>name resolution</primary> 1480 </indexterm> 1481 All DNS name resolution should be handled locally. To ensure that the server is configured 1482 correctly to handle this, edit <filename>/etc/resolv.conf</filename> to have the following 1483 content: 1484<screen> 1485search abmas.us abmas.biz 1486nameserver 127.0.0.1 1487nameserver 123.45.54.23 1488</screen> 1489 <indexterm> 1490 <primary>DNS server</primary> 1491 </indexterm> 1492 This instructs the name resolver function (when configured correctly) to ask the DNS server 1493 that is running locally to resolve names to addresses. In the event that the local name server 1494 is not available, ask the name server provided by the ISP. The latter, of course, does not resolve 1495 purely local names to IP addresses. 1496 </para></step> 1497 1498 <step><para> 1499 <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> 1500 The final step is to edit the <filename>/etc/nsswitch.conf</filename> file. 1501 This file controls the operation of the various resolver libraries that are part of the Linux 1502 Glibc libraries. Edit this file so that it contains the following entries: 1503<screen> 1504hosts: files dns wins 1505</screen> 1506 </para></step> 1507 </procedure> 1508 1509 <para> 1510 The basic DHCP and DNS services are now ready for validation testing. Before you can proceed, 1511 there are a few more steps along the road. First, configure the print spooling and print 1512 processing system. Then you can configure the server so that all services 1513 start automatically on reboot. You must also manually start all services prior to validation testing. 1514 </para> 1515 1516 </sect2> 1517 1518 <sect2 id="ch4ptrcfg"> 1519 <title>Printer Configuration</title> 1520 1521 <para> 1522 Network administrators who are new to CUPS based-printing typically experience some difficulty mastering 1523 its powerful features. The steps outlined in this section are designed to navigate around the distractions 1524 of learning CUPS. Instead of implementing smart features and capabilities, our approach is to use it as a 1525 transparent print queue that performs no filtering, and only minimal handling of each print job that is 1526 submitted to it. In other words, our configuration turns CUPS into a raw-mode print queue. This means that 1527 the correct printer driver must be installed on all clients. 1528 </para> 1529 1530 <procedure> 1531 <title>Printer Configuration Steps</title> 1532 1533 <step><para> 1534 Configure each printer to be a DHCP client, carefully following the manufacturer's guidelines. 1535 </para></step> 1536 1537 <step><para> 1538 Follow the instructions in the printer manufacturer's manuals to permit printing to port 9100. 1539 Use any other port the manufacturer specifies for direct-mode raw printing, and adjust the 1540 port as necessary in the following example commands. 1541 This allows the CUPS spooler to print using raw mode protocols. 1542 <indexterm><primary>CUPS</primary></indexterm> 1543 <indexterm><primary>raw printing</primary></indexterm> 1544 </para></step> 1545 1546 <step><para> 1547 <indexterm><primary>CUPS</primary><secondary>queue</secondary></indexterm><indexterm> 1548 <primary>lpadmin</primary> 1549 </indexterm> 1550 Configure the CUPS Print Queues as follows: 1551<screen> 1552&rootprompt; lpadmin -p qmsa -v socket://qmsa.abmas.biz:9100 -E 1553&rootprompt; lpadmin -p hplj6a -v socket://hplj6a.abmas.biz:9100 -E 1554&rootprompt; lpadmin -p qmsf -v socket://qmsf.abmas.biz:9100 -E 1555&rootprompt; lpadmin -p hplj6f -v socket://hplj6f.abmas.biz:9100 -E 1556</screen> 1557 <indexterm><primary>print filter</primary></indexterm> 1558 This creates the necessary print queues with no assigned print filter. 1559 </para></step> 1560 1561 <step><para><indexterm> 1562 <primary>enable</primary> 1563 </indexterm> 1564 Print queues may not be enabled at creation. Use <command>lpc stat</command> to check 1565 the status of the print queues and, if necessary, make certain that the queues you have 1566 just created are enabled by executing the following: 1567<screen> 1568&rootprompt; /usr/bin/enable qmsa 1569&rootprompt; /usr/bin/enable hplj6a 1570&rootprompt; /usr/bin/enable qmsf 1571&rootprompt; /usr/bin/enable hplj6f 1572</screen> 1573 </para></step> 1574 1575 <step><para><indexterm> 1576 <primary>accept</primary> 1577 </indexterm> 1578 Even though your print queues may be enabled, it is still possible that they 1579 are not accepting print jobs. A print queue services incoming printing 1580 requests only when configured to do so. Ensure that your print queues are 1581 set to accept incoming jobs by executing the following commands: 1582<screen> 1583&rootprompt; /usr/sbin/accept qmsa 1584&rootprompt; /usr/sbin/accept hplj6a 1585&rootprompt; /usr/sbin/accept qmsf 1586&rootprompt; /usr/sbin/accept hplj6f 1587</screen> 1588 </para></step> 1589 1590 <step><para> 1591 <indexterm><primary>mime type</primary></indexterm> 1592 <indexterm><primary>/etc/mime.convs</primary></indexterm> 1593 <indexterm><primary>application/octet-stream</primary></indexterm> 1594 Edit the file <filename>/etc/cups/mime.convs</filename> to uncomment the line: 1595<screen> 1596application/octet-stream application/vnd.cups-raw 0 - 1597</screen> 1598 </para></step> 1599 1600 <step><para> 1601 <indexterm><primary>/etc/mime.types</primary></indexterm> 1602 Edit the file <filename>/etc/cups/mime.types</filename> to uncomment the line: 1603<screen> 1604application/octet-stream 1605</screen> 1606 </para></step> 1607 1608 <step><para> 1609 Printing drivers are installed on each network client workstation. 1610 </para></step> 1611 </procedure> 1612 1613 <para> 1614 Note: If the parameter <parameter>cups options = Raw</parameter> is specified in the &smb.conf; file, 1615 the last two steps can be omitted with CUPS version 1.1.18, or later. 1616 </para> 1617 1618 <para> 1619 The UNIX system print queues have been configured and are ready for validation testing. 1620 </para> 1621 1622 </sect2> 1623 1624 <sect2 id="procstart"> 1625 <title>Process Startup Configuration</title> 1626 1627 <para> 1628 <indexterm><primary>chkconfig</primary></indexterm> 1629 There are two essential steps to process startup configuration. First, the process 1630 must be configured so that it automatically restarts each time the server 1631 is rebooted. This step involves use of the <command>chkconfig</command> tool that 1632 creates the appropriate symbolic links from the master daemon control file that is 1633 located in the <filename>/etc/rc.d</filename> directory, to the <filename>/etc/rc'x'.d</filename> 1634 directories. Links are created so that when the system run level is changed, the 1635 necessary start or kill script is run. 1636 </para> 1637 1638 <para> 1639 <indexterm><primary>/etc/xinetd.d</primary></indexterm> 1640 <indexterm><primary>inetd</primary></indexterm> 1641 <indexterm><primary>xinetd</primary></indexterm> 1642 <indexterm><primary>chkconfig</primary></indexterm> 1643 <indexterm><primary>super daemon</primary></indexterm> 1644 In the event that a service is not run as a daemon, but via the internetworking 1645 super daemon (<command>inetd</command> or <command>xinetd</command>), then the <command>chkconfig</command> 1646 tool makes the necessary entries in the <filename>/etc/xinetd.d</filename> directory 1647 and sends a hang-up (HUP) signal to the the super daemon, thus forcing it to 1648 re-read its control files. 1649 </para> 1650 1651 <para> 1652 Last, each service must be started to permit system validation to proceed. 1653 </para> 1654 1655 <procedure> 1656 <step><para> 1657 Use the standard system tool to configure each service to restart 1658 automatically at every system reboot. For example, 1659 <indexterm><primary>chkconfig</primary></indexterm> 1660<screen> 1661&rootprompt; chkconfig dhpcd on 1662&rootprompt; chkconfig named on 1663&rootprompt; chkconfig cups on 1664&rootprompt; chkconfig smb on 1665</screen> 1666 </para></step> 1667 1668 <step><para> 1669 <indexterm><primary>starting dhcpd</primary></indexterm> 1670 <indexterm><primary>starting samba</primary></indexterm> 1671 <indexterm><primary>starting CUPS</primary></indexterm> 1672 Now start each service to permit the system to be validated. 1673 Execute each of the following in the sequence shown: 1674 1675<screen> 1676&rootprompt; /etc/rc.d/init.d/dhcpd restart 1677&rootprompt; /etc/rc.d/init.d/named restart 1678&rootprompt; /etc/rc.d/init.d/cups restart 1679&rootprompt; /etc/rc.d/init.d/smb restart 1680</screen> 1681 </para></step> 1682 </procedure> 1683 1684 </sect2> 1685 1686 <sect2 id="ch4valid"> 1687 <title>Validation</title> 1688 1689 <para> 1690 <indexterm><primary>validation</primary></indexterm> 1691 Complex networking problems are most often caused by simple things that are poorly or incorrectly 1692 configured. The validation process adopted here should be followed carefully; it is the result of the 1693 experience gained from years of making and correcting the most common mistakes. Shortcuts often lead to basic errors. You should 1694 refrain from taking shortcuts, from making basic assumptions, and from not exercising due process 1695 and diligence in network validation. By thoroughly testing and validating every step in the process 1696 of network installation and configuration, you can save yourself from sleepless nights and restless 1697 days. A well debugged network is a foundation for happy network users and network administrators. 1698 Later in this book you learn how to make users happier. For now, it is enough to learn to 1699 validate. Let's get on with it. 1700 </para> 1701 1702 <procedure> 1703 <title>Server Validation Steps</title> 1704 1705 <step><para> 1706 <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> 1707 One of the most important facets of Samba configuration is to ensure that 1708 name resolution functions correctly. You can check name resolution 1709 with a few simple tests. The most basic name resolution is provided from the 1710 <filename>/etc/hosts</filename> file. To test its operation, make a 1711 temporary edit to the <filename>/etc/nsswitch.conf</filename> file. Using 1712 your favorite editor, change the entry for <constant>hosts</constant> to read: 1713<screen> 1714hosts: files 1715</screen> 1716 When you have saved this file, execute the following command: 1717<screen> 1718&rootprompt; ping diamond 1719PING sleeth1.abmas.biz (192.168.1.1) 56(84) bytes of data. 172064 bytes from sleeth1 (192.168.1.1): icmp_seq=1 ttl=64 time=0.131 ms 172164 bytes from sleeth1 (192.168.1.1): icmp_seq=2 ttl=64 time=0.179 ms 172264 bytes from sleeth1 (192.168.1.1): icmp_seq=3 ttl=64 time=0.192 ms 172364 bytes from sleeth1 (192.168.1.1): icmp_seq=4 ttl=64 time=0.191 ms 1724 1725--- sleeth1.abmas.biz ping statistics --- 17264 packets transmitted, 4 received, 0% packet loss, time 3016ms 1727rtt min/avg/max/mdev = 0.131/0.173/0.192/0.026 ms 1728</screen> 1729 This proves that name resolution via the <filename>/etc/hosts</filename> file 1730 is working. 1731 </para></step> 1732 1733 <step><para> 1734 <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> 1735 So far, your installation is going particularly well. In this step we validate 1736 DNS server and name resolution operation. Using your favorite UNIX system editor, 1737 change the <filename>/etc/nsswitch.conf</filename> file so that the 1738 <constant>hosts</constant> entry reads: 1739<screen> 1740hosts: dns 1741</screen> 1742 </para></step> 1743 1744 <step><para> 1745 <indexterm><primary>named</primary></indexterm> 1746 Before you test DNS operation, it is a good idea to verify that the DNS server 1747 is running by executing the following: 1748<screen> 1749&rootprompt; ps ax | grep named 1750 437 ? S 0:00 /sbin/syslogd -a /var/lib/named/dev/log 1751 524 ? S 0:00 /usr/sbin/named -t /var/lib/named -u named 1752 525 ? S 0:00 /usr/sbin/named -t /var/lib/named -u named 1753 526 ? S 0:00 /usr/sbin/named -t /var/lib/named -u named 1754 529 ? S 0:00 /usr/sbin/named -t /var/lib/named -u named 1755 540 ? S 0:00 /usr/sbin/named -t /var/lib/named -u named 1756 2552 pts/2 S 0:00 grep named 1757</screen> 1758 This means that we are ready to check DNS operation. Do so by executing: 1759 <indexterm><primary>ping</primary></indexterm> 1760<screen> 1761&rootprompt; ping diamond 1762PING sleeth1.abmas.biz (192.168.1.1) 56(84) bytes of data. 176364 bytes from sleeth1 (192.168.1.1): icmp_seq=1 ttl=64 time=0.156 ms 176464 bytes from sleeth1 (192.168.1.1): icmp_seq=2 ttl=64 time=0.183 ms 1765 1766--- sleeth1.abmas.biz ping statistics --- 17672 packets transmitted, 2 received, 0% packet loss, time 999ms 1768rtt min/avg/max/mdev = 0.156/0.169/0.183/0.018 ms 1769</screen> 1770 You should take a few more steps to validate DNS server operation, as follows: 1771<screen> 1772&rootprompt; host -f diamond.abmas.biz 1773sleeth1.abmas.biz has address 192.168.1.1 1774</screen> 1775 <indexterm><primary>/etc/hosts</primary></indexterm> 1776 You may now remove the entry called <constant>diamond</constant> from the 1777 <filename>/etc/hosts</filename> file. It does not hurt to leave it there, 1778 but its removal reduces the number of administrative steps for this name. 1779 </para></step> 1780 1781 <step><para> 1782 <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> 1783 WINS is a great way to resolve NetBIOS names to their IP address. You can test 1784 the operation of WINS by starting <command>nmbd</command> (manually or by way 1785 of the Samba startup method shown in <link linkend="procstart"/>). You must edit 1786 the <filename>/etc/nsswitch.conf</filename> file so that the <constant>hosts</constant> 1787 entry is as follows: 1788<screen> 1789hosts: wins 1790</screen> 1791 The next step is to make certain that Samba is running using <command>ps ax | grep mbd</command>. 1792 The <command>nmbd</command> daemon will provide the WINS name resolution service when the 1793 &smb.conf; file <smbconfsection name="global"/> parameter <smbconfoption name="wins 1794 support">Yes</smbconfoption> has been specified. Having validated that Samba is operational, 1795 excute the following: 1796<screen> 1797&rootprompt; ping diamond 1798PING diamond (192.168.1.1) 56(84) bytes of data. 179964 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=0.094 ms 180064 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=0.479 ms 1801</screen> 1802 <indexterm><primary>ping</primary></indexterm> 1803 Now that you can relax with the knowledge that all three major forms of name 1804 resolution to IP address resolution are working, edit the <filename>/etc/nsswitch.conf</filename> 1805 again. This time you add all three forms of name resolution to this file. 1806 Your edited entry for <constant>hosts</constant> should now look like this: 1807<screen> 1808hosts: files dns wins 1809</screen> 1810 The system is looking good. Let's move on. 1811 </para></step> 1812 1813 <step><para> 1814 It would give you peace of mind to know that the DHCP server is running 1815 and available for service. You can validate DHCP services by running: 1816 1817<screen> 1818&rootprompt; ps ax | grep dhcp 1819 2618 ? S 0:00 /usr/sbin/dhcpd ... 1820 8180 pts/2 S 0:00 grep dhcp 1821</screen> 1822 This shows that the server is running. The proof of whether or not it is working 1823 comes when you try to add the first DHCP client to the network. 1824 </para></step> 1825 1826 <step><para> 1827 <indexterm><primary>testparm</primary></indexterm> 1828 This is a good point at which to start validating Samba operation. You are 1829 content that name resolution is working for basic TCP/IP needs. Let's move on. 1830 If your &smb.conf; file has bogus options or parameters, this may cause Samba 1831 to refuse to start. The first step should always be to validate the contents 1832 of this file by running: 1833<screen> 1834&rootprompt; testparm -s 1835Load smb config files from smb.conf 1836Processing section "[homes]" 1837Processing section "[printers]" 1838Processing section "[netlogon]" 1839Processing section "[profiles]" 1840Processing section "[accounts]" 1841Processing section "[service]" 1842Processing section "[apps]" 1843Loaded services file OK. 1844# Global parameters 1845[global] 1846 workgroup = PROMISES 1847 netbios name = DIAMOND 1848 interfaces = eth1, eth2, lo 1849 bind interfaces only = Yes 1850 passdb backend = tdbsam 1851 pam password change = Yes 1852 passwd program = /usr/bin/passwd '%u' 1853 passwd chat = *New*Password* %n\n \ 1854 *Re-enter*new*password* %n\n *Password*changed* 1855 username map = /etc/samba/smbusers 1856 unix password sync = Yes 1857 log level = 1 1858 syslog = 0 1859 log file = /var/log/samba/%m 1860 max log size = 50 1861 smb ports = 139 1862 name resolve order = wins bcast hosts 1863 time server = Yes 1864 printcap name = CUPS 1865 show add printer wizard = No 1866 add user script = /usr/sbin/useradd -m '%u' 1867 delete user script = /usr/sbin/userdel -r '%u' 1868 add group script = /usr/sbin/groupadd '%g' 1869 delete group script = /usr/sbin/groupdel '%g' 1870 add user to group script = /usr/sbin/usermod -G '%g' '%u' 1871 add machine script = /usr/sbin/useradd \ 1872 -s /bin/false -d /dev/null '%u' 1873 shutdown script = /var/lib/samba/scripts/shutdown.sh 1874 abort shutdown script = /sbin/shutdown -c 1875 logon script = scripts\logon.bat 1876 logon path = \\%L\profiles\%U 1877 logon drive = X: 1878 logon home = \\%L\%U 1879 domain logons = Yes 1880 preferred master = Yes 1881 wins support = Yes 1882 utmp = Yes 1883 winbind use default domain = Yes 1884 map acl inherit = Yes 1885 cups options = Raw 1886 veto files = /*.eml/*.nws/*.{*}/ 1887 veto oplock files = /*.doc/*.xls/*.mdb/ 1888 1889[homes] 1890 comment = Home Directories 1891 valid users = %S 1892 read only = No 1893 browseable = No 1894... 1895### Remainder cut to save space ### 1896</screen> 1897 Clear away all errors before proceeding. 1898 </para></step> 1899 1900 <step><para> 1901 <indexterm><primary>check samba daemons</primary></indexterm> 1902 <indexterm><primary>smbd</primary></indexterm> 1903 <indexterm><primary>nmbd</primary></indexterm> 1904 <indexterm><primary>winbindd</primary></indexterm> 1905 Check that the Samba server is running: 1906<screen> 1907&rootprompt; ps ax | grep mbd 190814244 ? S 0:00 /usr/sbin/nmbd -D 190914245 ? S 0:00 /usr/sbin/nmbd -D 191014290 ? S 0:00 /usr/sbin/smbd -D 1911 1912$rootprompt; ps ax | grep winbind 191314293 ? S 0:00 /usr/sbin/winbindd -D 191414295 ? S 0:00 /usr/sbin/winbindd -D 1915</screen> 1916 The <command>winbindd</command> daemon is running in split mode (normal), so there are also 1917 two instances<footnote><para>For more information regarding winbindd, see <emphasis>TOSHARG2</emphasis>, 1918 Chapter 23, Section 23.3. The single instance of <command>smbd</command> is normal. One additional 1919 <command>smbd</command> slave process is spawned for each SMB/CIFS client 1920 connection.</para></footnote> of it. 1921 </para></step> 1922 1923 <step><para> 1924 <indexterm><primary>anonymous 1925 connection</primary></indexterm> 1926 <indexterm> 1927 <primary>smbclient</primary> 1928 </indexterm> 1929 Check that an anonymous connection can be made to the Samba server: 1930<screen> 1931&rootprompt; smbclient -L localhost -U% 1932 1933 Sharename Type Comment 1934 --------- ---- ------- 1935 IPC$ IPC IPC Service (Samba 3.0.20) 1936 netlogon Disk Network Logon Service 1937 profiles Disk Profile Share 1938 accounts Disk Accounting Files 1939 service Disk Financial Services Files 1940 apps Disk Application Files 1941 ADMIN$ IPC IPC Service (Samba 3.0.20) 1942 hplj6a Printer hplj6a 1943 hplj6f Printer hplj6f 1944 qmsa Printer qmsa 1945 qmsf Printer qmsf 1946 1947 Server Comment 1948 --------- ------- 1949 DIAMOND Samba 3.0.20 1950 1951 Workgroup Master 1952 --------- ------- 1953 PROMISES DIAMOND 1954</screen> 1955 This demonstrates that an anonymous listing of shares can be obtained. This is the equivalent 1956 of browsing the server from a Windows client to obtain a list of shares on the server. 1957 The <constant>-U%</constant> argument means to send a <constant>NULL</constant> username and 1958 a <constant>NULL</constant> password. 1959 </para></step> 1960 1961 <step><para> 1962 <indexterm><primary>dhcp client validation</primary></indexterm> 1963 <indexterm><primary>printer validation</primary></indexterm> 1964 <indexterm><primary>arp</primary></indexterm> 1965 Verify that each printer has the IP address assigned in the DHCP server configuration file. 1966 The easiest way to do this is to ping the printer name. Immediately after the ping response 1967 has been received, execute <command>arp -a</command> to find the MAC address of the printer 1968 that has responded. Now you can compare the IP address and the MAC address of the printer 1969 with the configuration information in the <filename>/etc/dhcpd.conf</filename> file. They 1970 should, of course, match. For example, 1971<screen> 1972&rootprompt; ping hplj6 1973PING hplj6a (192.168.1.30) 56(84) bytes of data. 197464 bytes from hplj6a (192.168.1.30): icmp_seq=1 ttl=64 time=0.113 ms 1975 1976&rootprompt; arp -a 1977hplj6a (192.168.1.30) at 00:03:47:CB:81:E0 [ether] on eth0 1978</screen> 1979 <indexterm> 1980 <primary>/etc/dhcpd.conf</primary> 1981 </indexterm> 1982 The MAC address <constant>00:03:47:CB:81:E0</constant> matches that specified for the 1983 IP address from which the printer has responded and with the entry for it in the 1984 <filename>/etc/dhcpd.conf</filename> file. Repeat this for each printer configured. 1985 </para></step> 1986 1987 <step><para> 1988 <indexterm><primary>authenticated connection</primary></indexterm> 1989 Make an authenticated connection to the server using the <command>smbclient</command> tool: 1990<screen> 1991&rootprompt; smbclient //diamond/accounts -U gholmes 1992Password: XXXXXXX 1993smb: \> dir 1994 . D 0 Thu Nov 27 15:07:09 2003 1995 .. D 0 Sat Nov 15 17:40:50 2003 1996 zakadmin.exe 161424 Thu Nov 27 15:06:52 2003 1997 zak.exe 6066384 Thu Nov 27 15:06:52 2003 1998 dhcpd.conf 1256 Thu Nov 27 15:06:52 2003 1999 smb.conf 2131 Thu Nov 27 15:06:52 2003 2000 initGrps.sh A 1089 Thu Nov 27 15:06:52 2003 2001 POLICY.EXE 86542 Thu Nov 27 15:06:52 2003 2002 2003 55974 blocks of size 65536. 33968 blocks available 2004smb: \> q 2005</screen> 2006 </para></step> 2007 2008 <step><para> 2009 <indexterm><primary>nmap</primary></indexterm> 2010 Your new server is connected to an Internet-accessible connection. Before you start 2011 your firewall, you should run a port scanner against your system. You should repeat that 2012 after the firewall has been started. This helps you understand to what extent the 2013 server may be vulnerable to external attack. One way you can do this is by using an 2014 external service, such as the <ulink url="http://www.dslreports.com/scan">DSL Reports</ulink> 2015 tools. Alternately, if you can gain root-level access to a remote 2016 UNIX/Linux system that has the <command>nmap</command> tool, you can run the following: 2017<screen> 2018&rootprompt; nmap -v -sT server.abmas.us 2019 2020Starting nmap V. 3.00 ( www.insecure.org/nmap/ ) 2021Host server.abmas.us (123.45.67.66) appears to be up ... good. 2022Initiating Connect() Scan against server.abmas.us (123.45.67.66) 2023Adding open port 6000/tcp 2024Adding open port 873/tcp 2025Adding open port 445/tcp 2026Adding open port 10000/tcp 2027Adding open port 901/tcp 2028Adding open port 631/tcp 2029Adding open port 25/tcp 2030Adding open port 111/tcp 2031Adding open port 32770/tcp 2032Adding open port 3128/tcp 2033Adding open port 53/tcp 2034Adding open port 80/tcp 2035Adding open port 443/tcp 2036Adding open port 139/tcp 2037Adding open port 22/tcp 2038The Connect() Scan took 0 seconds to scan 1601 ports. 2039Interesting ports on server.abmas.us (123.45.67.66): 2040(The 1587 ports scanned but not shown below are in state: closed) 2041Port State Service 204222/tcp open ssh 204325/tcp open smtp 204453/tcp open domain 204580/tcp open http 2046111/tcp open sunrpc 2047139/tcp open netbios-ssn 2048443/tcp open https 2049445/tcp open microsoft-ds 2050631/tcp open ipp 2051873/tcp open rsync 2052901/tcp open samba-swat 20533128/tcp open squid-http 20546000/tcp open X11 205510000/tcp open snet-sensor-mgmt 205632770/tcp open sometimes-rpc3 2057 2058Nmap run completed -- 1 IP address (1 host up) scanned in 1 second 2059</screen> 2060 The above scan was run before the external interface was locked down with the NAT-firewall 2061 script you created above. The following results are obtained after the firewall rules 2062 have been put into place: 2063<screen> 2064&rootprompt; nmap -v -sT server.abmas.us 2065 2066Starting nmap V. 3.00 ( www.insecure.org/nmap/ ) 2067Host server.abmas.us (123.45.67.66) appears to be up ... good. 2068Initiating Connect() Scan against server.abmas.us (123.45.67.66) 2069Adding open port 53/tcp 2070Adding open port 22/tcp 2071The Connect() Scan took 168 seconds to scan 1601 ports. 2072Interesting ports on server.abmas.us (123.45.67.66): 2073(The 1593 ports scanned but not shown below are in state: filtered) 2074Port State Service 207522/tcp open ssh 207625/tcp closed smtp 207753/tcp open domain 207880/tcp closed http 2079443/tcp closed https 2080 2081Nmap run completed -- 1 IP address (1 host up) scanned in 168 seconds 2082</screen> 2083 </para></step> 2084 2085 </procedure> 2086 2087 </sect2> 2088 2089 <sect2 id="ch4appscfg"> 2090 <title>Application Share Configuration</title> 2091 2092 <para> 2093 <indexterm><primary>application server</primary></indexterm> 2094 <indexterm><primary>administrative installation</primary></indexterm> 2095 The use of an application server is a key mechanism by which desktop administration overheads 2096 can be reduced. Check the application manual for your software to identify how best to 2097 create an administrative installation. 2098 </para> 2099 2100 <para> 2101 Some Windows software will only run locally on the desktop computer. Such software 2102 is typically not suited for administrative installation. Administratively installed software 2103 permits one or more of the following installation choices: 2104 </para> 2105 2106 <itemizedlist> 2107 <listitem><para> 2108 Install software fully onto a workstation, storing data files on the same workstation. 2109 </para></listitem> 2110 2111 <listitem><para> 2112 Install software fully onto a workstation with central network data file storage. 2113 </para></listitem> 2114 2115 <listitem><para> 2116 Install software to run off a central application server with data files stored 2117 on the local workstation. This is often called a minimum installation, or a 2118 network client installation. 2119 </para></listitem> 2120 2121 <listitem><para> 2122 Install software to run off a central application server with data files stored 2123 on a central network share. This type of installation often prevents storage 2124 of work files on the local workstation. 2125 </para></listitem> 2126 </itemizedlist> 2127 2128 <para> 2129 <indexterm><primary></primary></indexterm> 2130 A common application deployed in this environment is an office suite. 2131 Enterprise editions of Microsoft Office XP Professional can be administratively installed 2132 by launching the installation from a command shell. The command that achieves this is 2133 <command>setup /a</command>. It results in a set of prompts through which various 2134 installation choices can be made. Refer to the Microsoft Office Resource SDK and Resource 2135 Kit for more information regarding this mode of installation of MS Office XP Professional. 2136 The full administrative installation of MS Office XP Professional requires approximately 2137 650 MB of disk space. 2138 </para> 2139 2140 <para> 2141 When the MS Office XP Professional product has been installed to the administrative network 2142 share, the product can be installed onto a workstation by executing the normal setup program. 2143 The installation process now provides a choice to either perform a minimum installation 2144 or a full local installation. A full local installation takes over 100 MB of disk space. 2145 A network workstation (minimum) installation requires typically 10 MB to 15 MB of 2146 local disk space. In the latter case, when the applications are used, they load over the network. 2147 </para> 2148 2149 <para> 2150 <indexterm><primary>Service Packs</primary></indexterm> 2151 <indexterm><primary>Microsoft Office</primary></indexterm> 2152 Microsoft Office Service Packs can be unpacked to update an administrative share. This makes 2153 it possible to update MS Office XP Professional for all users from a single installation 2154 of the service pack and generally circumvents the need to run updates on each network 2155 Windows client. 2156 </para> 2157 2158 <para> 2159 The default location for MS Office XP Professional data files can be set through registry 2160 editing or by way of configuration options inside each Office XP Professional application. 2161 </para> 2162 2163 <para> 2164 <indexterm><primary>OpenOffice</primary></indexterm> 2165 OpenOffice.Org OpenOffice Version 1.1.0 can be installed locally. It can also 2166 be installed to run off a network share. The latter is a most desirable solution for office-bound 2167 network users and for administrative staff alike. It permits quick and easy updates 2168 to be rolled out to all users with a minimum of disruption and with maximum flexibility. 2169 </para> 2170 2171 <para> 2172 The process for installation of administrative shared OpenOffice involves download of the 2173 distribution ZIP file, followed by extraction of the ZIP file into a temporary disk area. 2174 When fully extracted using the unzipping tool of your choosing, change into the Windows 2175 installation files directory then execute <command>setup -net</command>. You are 2176 prompted on screen for the target installation location. This is the administrative 2177 share point. The full administrative OpenOffice share takes approximately 150 MB of disk 2178 space. 2179 </para> 2180 2181 <sect3> 2182 <title>Comments Regarding Software Terms of Use</title> 2183 <para> 2184 Many single-user products can be installed into an administrative share, but 2185 personal versions of products such as Microsoft Office XP Professional do not permit this. 2186 Many people do not like terms of use typical with commercial products, so a few comments 2187 regarding software licensing seem important. 2188 </para> 2189 2190 <para> 2191 Please do not use an administrative installation of proprietary and commercially licensed 2192 software products to violate the copyright holders' property. All software is licensed, 2193 particularly software that is licensed for use free of charge. All software is the property 2194 of the copyright holder unless the author and/or copyright holder has explicitly disavowed 2195 ownership and has placed the software into the public domain. 2196 </para> 2197 2198 <para> 2199 Software that is under the GNU General Public License, like proprietary software, is 2200 licensed in a way that restricts use. For example, if you modify GPL software and then 2201 distribute the binary version of your modifications, you must offer to provide the source 2202 code as well. This restriction is designed to maintain the momentum 2203 of the diffusion of technology and to protect against the withholding of innovations. 2204 </para> 2205 2206 <para> 2207 Commercial and proprietary software generally restrict use to those who have paid the 2208 license fees and who comply with the licensee's terms of use. Software that is released 2209 under the GNU General Public License is restricted to particular terms and conditions 2210 also. Whatever the licensing terms may be, if you do not approve of the terms of use, 2211 please do not use the software. 2212 </para> 2213 2214 <para> 2215 <indexterm><primary>GPL</primary></indexterm> 2216 Samba is provided under the terms of the GNU GPL Version 2, a copy of which is provided 2217 with the source code. 2218 </para> 2219 </sect3> 2220 2221 </sect2> 2222 2223 <sect2 id="ch4wincfg"> 2224 <title>Windows Client Configuration</title> 2225 2226 <para> 2227 Christine needs to roll out 130 new desktop systems. There is no doubt that she also needs 2228 to reinstall many of the notebook computers that will be recycled for use with the new network 2229 configuration. The smartest way to handle the challenge of the roll-out program is to build 2230 a staged system for each type of target machine, and then use an image replication tool such as Norton 2231 Ghost (enterprise edition) to replicate the staged machine to its target desktops. The same can 2232 be done with notebook computers as long as they are identical or sufficiently similar. 2233 </para> 2234 2235 <procedure id="sbewinclntprep"> 2236 <title>Windows Client Configuration Procedure</title> 2237 2238 <step><para> 2239 <indexterm><primary>WINS</primary></indexterm> 2240 <indexterm><primary>DHCP</primary></indexterm> 2241 Install MS Windows XP Professional. During installation, configure the client to use DHCP for 2242 TCP/IP protocol configuration. DHCP configures all Windows clients to use the WINS Server 2243 address that has been defined for the local subnet. 2244 </para></step> 2245 2246 <step><para> 2247 Join the Windows Domain <constant>PROMISES</constant>. Use the Domain Administrator 2248 username <constant>root</constant> and the SMB password you assigned to this account. 2249 A detailed step-by-step procedure for joining a Windows 200x/XP Professional client to 2250 a Windows Domain is given in <link linkend="appendix"/>, <link linkend="domjoin"/>. 2251 Reboot the machine as prompted and then log on using the Domain Administrator account 2252 (<constant>root</constant>). 2253 </para></step> 2254 2255 <step><para> 2256 Verify <constant>DIAMOND</constant> is visible in <guimenu>My Network Places</guimenu>, 2257 that it is possible to connect to it and see the shares <guimenuitem>accounts</guimenuitem>, 2258 <guimenuitem>apps</guimenuitem>, and <guimenuitem>finsvcs</guimenuitem>, and that it is 2259 possible to open each share to reveal its contents. 2260 </para></step> 2261 2262 <step><para> 2263 Create a drive mapping to the <constant>apps</constant> share on the server <constant>DIAMOND</constant>. 2264 </para></step> 2265 2266 <step><para> 2267 Perform an administrative installation of each application to be used. Select the options 2268 that you wish to use. Of course, you can choose to run applications over the network, correct? 2269 </para></step> 2270 2271 <step><para> 2272 Now install all applications to be installed locally. Typical tools include Adobe Acrobat, 2273 NTP-based time synchronization software, drivers for specific local devices such as fingerprint 2274 scanners, and the like. Probably the most significant application for local installation 2275 is antivirus software. 2276 </para></step> 2277 2278 <step><para> 2279 Now install all four printers onto the staging system. The printers you install 2280 include the accounting department HP LaserJet 6 and Minolta QMS Magicolor printers. You will 2281 also configure identical printers that are located in the financial services department. 2282 Install printers on each machine following the steps shown in the Windows client printer 2283 preparation procedure below. 2284 </para></step> 2285 2286 <step><para> 2287 <indexterm><primary>defragmentation</primary></indexterm> 2288 When you are satisfied that the staging systems are complete, use the appropriate procedure to 2289 remove the client from the domain. Reboot the system and then log on as the local administrator 2290 and clean out all temporary files stored on the system. Before shutting down, use the disk 2291 defragmentation tool so that the file system is in optimal condition before replication. 2292 </para></step> 2293 2294 <step><para> 2295 Boot the workstation using the Norton (Symantec) Ghosting diskette (or CD-ROM) and image the 2296 machine to a network share on the server. 2297 </para></step> 2298 2299 <step><para> 2300 <indexterm><primary>Windows security identifier</primary><see>SID</see></indexterm> 2301 <indexterm><primary>SID</primary></indexterm> 2302 You may now replicate the image to the target machines using the appropriate Norton Ghost 2303 procedure. Make sure to use the procedure that ensures each machine has a unique 2304 Windows security identifier (SID). When the installation of the disk image has completed, boot the PC. 2305 </para></step> 2306 2307 <step><para> 2308 Log on to the machine as the local Administrator (the only option), and join the machine to 2309 the Domain, following the procedure set out in <link linkend="appendix"/>, <link linkend="domjoin"/>. The system is now 2310 ready for the user to log on, provided you have created a network logon account for that 2311 user, of course. 2312 </para></step> 2313 2314 <step><para> 2315 Instruct all users to log on to the workstation using their assigned username and password. 2316 </para></step> 2317 </procedure> 2318 2319 <procedure id="sbewinclntptrprep"> 2320 <title>Windows Client Printer Preparation Procedure</title> 2321 2322 <step><para> 2323 Click <menuchoice> 2324 <guimenu>Start</guimenu> 2325 <guimenuitem>Settings</guimenuitem> 2326 <guimenuitem>Printers</guimenuitem> 2327 <guiicon>Add Printer</guiicon> 2328 <guibutton>Next</guibutton> 2329 </menuchoice>. Do not click <guimenuitem>Network printer</guimenuitem>. 2330 Ensure that <guimenuitem>Local printer</guimenuitem> is selected. 2331 </para></step> 2332 2333 <step><para> 2334 Click <guibutton>Next</guibutton>. In the 2335 <guimenuitem>Manufacturer:</guimenuitem> panel, select <constant>HP</constant>. 2336 In the <guimenuitem>Printers:</guimenuitem> panel, select the printer called 2337 <constant>HP LaserJet 6</constant>. Click <guibutton>Next</guibutton>. 2338 </para></step> 2339 2340 <step><para> 2341 In the <guimenuitem>Available ports:</guimenuitem> panel, select 2342 <constant>FILE:</constant>. Accept the default printer name by clicking 2343 <guibutton>Next</guibutton>. When asked, <quote>Would you like to print a 2344 test page?,</quote> click <guimenuitem>No</guimenuitem>. Click 2345 <guibutton>Finish</guibutton>. 2346 </para></step> 2347 2348 <step><para> 2349 You may be prompted for the name of a file to print to. If so, close the 2350 dialog panel. Right-click <menuchoice> 2351 <guiicon>HP LaserJet 6</guiicon> 2352 <guimenuitem>Properties</guimenuitem> 2353 <guisubmenu>Details (Tab)</guisubmenu> 2354 <guimenuitem>Add Port</guimenuitem> 2355 </menuchoice>. 2356 </para></step> 2357 2358 <step><para> 2359 In the <guimenuitem>Network</guimenuitem> panel, enter the name of 2360 the print queue on the Samba server as follows: <constant>\\DIAMOND\hplj6a</constant>. 2361 Click <menuchoice> 2362 <guibutton>OK</guibutton> 2363 <guibutton>OK</guibutton> 2364 </menuchoice> to complete the installation. 2365 </para></step> 2366 2367 <step><para> 2368 Repeat the printer installation steps above for both HP LaserJet 6 printers 2369 as well as for both QMS Magicolor laser printers. 2370 </para></step> 2371 </procedure> 2372 2373 </sect2> 2374 2375 <sect2> 2376 <title>Key Points Learned</title> 2377 2378 <para> 2379 How do you feel? You have built a capable network, a truly ambitious project. 2380 Future network updates can be handled by 2381 your staff. You must be a satisfied manager. Let's review the achievements. 2382 </para> 2383 2384 <itemizedlist> 2385 <listitem><para> 2386 A simple firewall has been configured to protect the server in the event that 2387 the ISP firewall service should fail. 2388 </para></listitem> 2389 2390 <listitem><para> 2391 The Samba configuration uses measures to ensure that only local network users 2392 can connect to SMB/CIFS services. 2393 </para></listitem> 2394 2395 <listitem><para> 2396 Samba uses the new <constant>tdbsam</constant> passdb backend facility. 2397 Considerable complexity was added to Samba functionality. 2398 </para></listitem> 2399 2400 <listitem><para> 2401 A DHCP server was configured to implement dynamic DNS (DDNS) updates to the DNS 2402 server. 2403 </para></listitem> 2404 2405 <listitem><para> 2406 The DNS server was configured to permit DDNS only for local network clients. This 2407 server also provides primary DNS services for the company Internet presence. 2408 </para></listitem> 2409 2410 <listitem><para> 2411 You introduced an application server as well as the concept of cloning a Windows 2412 client in order to effect improved standardization of desktops and to reduce 2413 the costs of network management. 2414 </para></listitem> 2415 </itemizedlist> 2416 2417 </sect2> 2418 2419</sect1> 2420 2421<sect1> 2422 <title>Questions and Answers</title> 2423 2424 <para> 2425 </para> 2426 2427 <qandaset defaultlable="missed01" type="number"> 2428 <qandaentry> 2429 <question> 2430 2431 <para> 2432 What is the maximum number of account entries that the <parameter>tdbsam</parameter> 2433 passdb backend can handle? 2434 </para> 2435 2436 </question> 2437 <answer> 2438 2439 <para> 2440 The tdb data structure and support system can handle more entries than the number of 2441 accounts that are possible on most UNIX systems. A practical limit would come into 2442 play long before a performance boundary would be anticipated. That practical limit 2443 is controlled by the nature of Windows networking. There are few Windows file and 2444 print servers that can handle more than a few hundred concurrent client connections. 2445 The key limiting factors that predicate offloading of services to additional servers 2446 are memory capacity, the number of CPUs, network bandwidth, and disk I/O limitations. 2447 All of these are readily exhausted by just a few hundred concurrent active users. 2448 Such bottlenecks can best be removed by segmentation of the network (distributing 2449 network load across multiple networks). 2450 </para> 2451 2452 <para> 2453 As the network grows, it becomes necessary to provide additional authentication 2454 servers (domain controllers). The tdbsam is limited to a single machine and cannot 2455 be reliably replicated. This means that practical limits on network design dictate 2456 the point at which a distributed passdb backend is required; at this time, there is 2457 no real alternative other than ldapsam (LDAP). 2458 </para> 2459 2460 <para> 2461 The guideline provided in <emphasis>TOSHARG2</emphasis>, Chapter 10, Section 10.1.2, 2462 is to limit the number of accounts in the tdbsam backend to 250. This is the point 2463 at which most networks tend to want backup domain controllers (BDCs). Samba-3 does 2464 not provide a mechanism for replicating tdbsam data so it can be used by a BDC. The 2465 limitation of 250 users per tdbsam is predicated only on the need for replication, 2466 not on the limits<footnote><para>Bench tests have shown that tdbsam is a very 2467 effective database technology. There is surprisingly little performance loss even 2468 with over 4000 users.</para></footnote> of the tdbsam backend itself. 2469 </para> 2470 2471 </answer> 2472 </qandaentry> 2473 2474 <qandaentry> 2475 <question> 2476 2477 <para> 2478 Would Samba operate any better if the OS level is set to a value higher than 35? 2479 </para> 2480 2481 </question> 2482 <answer> 2483 2484 <para> 2485 No. MS Windows workstations and servers do not use a value higher than 33. Setting this to a value 2486 of 35 already assures Samba of precedence over MS Windows products in browser elections. There is 2487 no gain to be had from setting this higher. 2488 </para> 2489 2490 </answer> 2491 </qandaentry> 2492 2493 <qandaentry> 2494 <question> 2495 2496 <para> 2497 Why in this example have you provided UNIX group to Windows Group mappings for only Domain Groups? 2498 </para> 2499 2500 </question> 2501 <answer> 2502 2503 <para> 2504 At this time, Samba has the capacity to use only Domain Groups mappings. It is possible that at 2505 a later date Samba may make use of Windows Local Groups, as well as of the Active Directory special 2506 Groups. Proper operation requires Domain Groups to be mapped to valid UNIX groups. 2507 </para> 2508 2509 </answer> 2510 </qandaentry> 2511 2512 <qandaentry> 2513 <question> 2514 2515 <para> 2516 Why has a path been specified in the <parameter>IPC$</parameter> share? 2517 </para> 2518 2519 </question> 2520 <answer> 2521 2522 <para> 2523 This is done so that in the event that a software bug may permit a client connection to the IPC$ share to 2524 obtain access to the file system, it does so at a location that presents least risk. Under normal operation 2525 this type of paranoid step should not be necessary. The use of this parameter should not be necessary. 2526 </para> 2527 2528 </answer> 2529 </qandaentry> 2530 2531 <qandaentry> 2532 <question> 2533 2534 <para> 2535 Why does the &smb.conf; file in this exercise include an entry for <smbconfoption name="smb ports"/>? 2536 </para> 2537 2538 </question> 2539 <answer> 2540 2541 <para> 2542 The default order by which Samba-3 attempts to communicate with MS Windows clients is via port 445 (the TCP port 2543 used by Windows clients when NetBIOS-less SMB over TCP/IP is in use). TCP port 139 is the primary port used for NetBIOS 2544 over TCP/IP. In this configuration Windows network operations are predicated around NetBIOS over TCP/IP. By 2545 specifying the use of only port 139, the intent is to reduce unsuccessful service connection attempts. 2546 The result of this is improved network performance. Where Samba-3 is installed as an Active Directory Domain 2547 member, the default behavior is highly beneficial and should not be changed. 2548 </para> 2549 2550 </answer> 2551 </qandaentry> 2552 2553 <qandaentry> 2554 <question> 2555 2556 <para> 2557 What is the difference between a print queue and a printer? 2558 </para> 2559 2560 </question> 2561 <answer> 2562 2563 <para> 2564 A printer is a physical device that is connected either directly to the network or to a computer 2565 via a serial, parallel, or USB connection so that print jobs can be submitted to it to create a 2566 hard copy printout. Network-attached printers that use TCP/IP-based printing generally accept a 2567 single print data stream and block all secondary attempts to dispatch jobs concurrently to the 2568 same device. If many clients were to concurrently print directly via TCP/IP to the same printer, 2569 it would result in a huge amount of network traffic through continually failing connection attempts. 2570 </para> 2571 2572 <para> 2573 A print server (like CUPS or LPR/LPD) accepts multiple concurrent input streams or 2574 print requests. When the data stream has been fully received, the input stream is closed, 2575 and the job is then submitted to a sequential print queue where the job is stored until 2576 the printer is ready to receive the job. 2577 </para> 2578 2579 </answer> 2580 </qandaentry> 2581 2582 <qandaentry> 2583 <question> 2584 2585 <para> 2586 Can all MS Windows application software be installed onto an application server share? 2587 </para> 2588 2589 </question> 2590 <answer> 2591 2592 <para> 2593 Much older Windows software is not compatible with installation to and execution from 2594 an application server. Enterprise versions of Microsoft Office XP Professional can 2595 be installed to an application server. Retail consumer versions of Microsoft Office XP 2596 Professional do not permit installation to an application server share and can be installed 2597 and used only to/from a local workstation hard disk. 2598 </para> 2599 2600 </answer> 2601 </qandaentry> 2602 2603 <qandaentry> 2604 <question> 2605 2606 <para> 2607 Why use dynamic DNS (DDNS)? 2608 </para> 2609 2610 </question> 2611 <answer> 2612 2613 <para> 2614 When DDNS records are updated directly from the DHCP server, it is possible for 2615 network clients that are not NetBIOS-enabled, and thus cannot use WINS, to locate 2616 Windows clients via DNS. 2617 </para> 2618 2619 </answer> 2620 </qandaentry> 2621 2622 <qandaentry> 2623 <question> 2624 2625 <para> 2626 Why would you use WINS as well as DNS-based name resolution? 2627 </para> 2628 2629 </question> 2630 <answer> 2631 2632 <para> 2633 WINS is to NetBIOS names as DNS is to fully qualified domain names (FQDN). The FQDN is 2634 a name like <quote>myhost.mydomain.tld</quote> where <parameter>tld</parameter> 2635 means <constant>top-level domain</constant>. A FQDN is a longhand but easy-to-remember 2636 expression that may be up to 1024 characters in length and that represents an IP address. 2637 A NetBIOS name is always 16 characters long. The 16<superscript>th</superscript> character 2638 is a name type indicator. A specific name type is registered<footnote><para> 2639 See <emphasis>TOSHARG2</emphasis>, Chapter 9, for more information.</para></footnote> for each 2640 type of service that is provided by the Windows server or client and that may be registered 2641 where a WINS server is in use. 2642 </para> 2643 2644 <para> 2645 WINS is a mechanism by which a client may locate the IP Address that corresponds to a 2646 NetBIOS name. The WINS server may be queried to obtain the IP Address for a NetBIOS name 2647 that includes a particular registered NetBIOS name type. DNS does not provide a mechanism 2648 that permits handling of the NetBIOS name type information. 2649 </para> 2650 2651 <para> 2652 DNS provides a mechanism by which TCP/IP clients may locate the IP address of a particular 2653 hostname or service name that has been registered in the DNS database for a particular domain. 2654 A DNS server has limited scope of control and is said to be authoritative for the zone over 2655 which it has control. 2656 </para> 2657 2658 <para> 2659 Windows 200x Active Directory requires the registration in the DNS zone for the domain it 2660 controls of service locator<footnote><para>See TOSHARG2, Chapter 9, Section 9.3.3.</para></footnote> records 2661 that Windows clients and servers will use to locate Kerberos and LDAP services. ADS also 2662 requires the registration of special records that are called global catalog (GC) entries 2663 and site entries by which domain controllers and other essential ADS servers may be located. 2664 </para> 2665 2666 </answer> 2667 </qandaentry> 2668 2669 <qandaentry> 2670 <question> 2671 2672 <para> 2673 What are the major benefits of using an application server? 2674 </para> 2675 2676 </question> 2677 <answer> 2678 2679 <para> 2680 The use of an application server can significantly reduce application update maintenance. 2681 By providing a centralized application share, software updates need be applied to only 2682 one location for all major applications used. This results in faster update roll-outs and 2683 significantly better application usage control. 2684 </para> 2685 2686 </answer> 2687 </qandaentry> 2688 2689 </qandaset> 2690 2691</sect1> 2692 2693</chapter> 2694