1<!doctype linuxdoc system> <!-- -*- SGML -*- -->
2<!--
3 v 0.1 23 Aug 1997 	Dan Shearer 
4			Original Samba-meta-FAQ.sgml from Paul's sambafaq.sgml
5 v 0.2 25 Aug 1997      Dan   
6 v 0.3 7  Oct 1997	Paul
7			Changed samba.canberra refs to samba.anu.../samba/
8-->
9
10<article>
11
12<title> Samba meta FAQ
13
14<author>Dan Shearer & Paul Blackman, <tt>ictinus@samba.org</tt>
15
16<date>v 0.3, 7 Oct '97
17
18<abstract> This is the meta-Frequently Asked Questions (FAQ) document
19for Samba, the free and very popular SMB and CIFS server product. It
20contains overview information for the Samba suite of programs, a
21quick-start guide, and pointers to all other Samba documentation. Other
22FAQs exist for specific client and server issues, and HOWTO documents
23for more extended topics to do with Samba software. Current to version
24Samba 1.9.17. Please send any corrections to the author. 
25</abstract>
26
27<toc>
28
29<sect> Quick Reference Guides to Samba Documentation<p><label id=quickref>
30
31We are endeavouring to provide links here to every major class of
32information about Samba or things related to Samba. We cannot list every
33document, but we are aiming for all documents to be at most two
34referrals from those listed here. This needs constant maintaining, so
35please send the author your feedback.
36
37<sect1> Samba for the Impatient<p><label id="impatient">
38
39You know you should read the documentation but can't wait to start? What
40you need to do then is follow the instructions in the following
41documents in the order given. This should be enough to get a fairly
42simple site going quickly. If you have any problems, refer back to this
43meta-FAQ and follow the links to find more reading material.
44
45<descrip>
46
47<label id="ImpGet"><tag/Getting Samba:/ The fastest way to get Samba
48going is and install it is to have an operating system for which the
49Samba team has put together an installation package. To see if your OS
50is included have a look at the directory
51/pub/samba/Binary_Packages/"OS_Vendor" on your nearest <url
52url="../MIRRORS" name="mirror site">. If it is included follow the
53installation instructions in the README file there and then do some <ref id="ImpTest"
54name="basic testing">. If you are not so fortunate, follow the normal <ref
55id="WhereFrom" name="download instructions"> and then continue with <ref
56id="ImpInst" name="building and installing Samba">.
57
58<label id="ImpInst"><tag/Building and Installing Samba:/ At the moment
59there are two kinds of Samba server installs besides the prepackaged
60binaries mentioned in the previous step. You need to decide if you have a <url url="../UNIX_INSTALL.txt"
61name="Unix or close relative"> or <url
62url="Samba-Server-FAQ.html#PortInfo" name="other supported operating system">.
63
64<label id="ImpTest"><tag/Basic Testing:/ Try to connect using the
65supplied smbclient command-line program. You need to know the IP
66hostname of your server. A service name must be defined in smb.conf, as
67given in the examples (under many operating systems if there is a
68[homes] service you can just use a valid username.) Then type
69<tt>
70        smbclient \\hostname\servicename
71</tt>
72Under most Unixes you will need to put the parameters within quotation
73marks. If this works, try connecting from one of the SMB clients you
74were planning to use with Samba.
75
76<label id="ImpDebug"><tag/Debug sequence:/ If you think you have completed the 
77previous step and things aren't working properly work through 
78<url url="../DIAGNOSIS.txt" name="the diagnosis recipe.">
79
80<label id="ImpExp"><tag/Exporting files to SMB clients:/ You should read the manual pages
81for smb.conf, but here is a <url url="Samba-Server-FAQ.html#Exporting"
82name="quick answer guide.">
83
84<label id="ImpControl"><tag/Controlling user access:/ the quickest and dirtiest way of sharing
85resources is to use <ref id="ShareModeSecurity" name="share level
86security."> If you want to spend more time and have a proper username
87and password database you must read the paragraph on <ref
88id="DomainModeSecurity" name="domain mode security."> If you want
89encryption (eg you are using Windows NT clients) follow the <url
90url="Samba-Server-FAQ.html#SMBEncryptionSteps" name="SMB encryption
91instructions.">
92
93<label id="ImpBrowse"><tag/Browsing:/ if you are happy to type in "\\samba-server\sharename"
94at the client end then do not read any further. Otherwise you need to
95understand the <ref id="BrowsingDefinitions" name="browsing terminology">
96and read <url url="Samba-Server-FAQ.html#NameBrowsing">. 
97
98<label id="ImpPrint"><tag/Printing:/ See the <url url="Samba-Server-FAQ.html#Printing"
99name="printing quick answer guide.">
100
101</descrip>
102
103If you have got everything working to this point, you can expect Samba
104to be stable and secure: these are its greatest strengths. However Samba
105has a great deal to offer and to go further you must do some more
106reading. Speed and security optimisations, printer accounting, network
107logons, roving profiles, browsing across multiple subnets and so on are
108all covered either in this document or in those it refers to.
109
110<sect1> All Samba Documentation<p><label id=AllDocs>
111
112<itemize>
113
114<item> Meta-FAQ. This is the mother of all documents, and is the one you
115are reading now. The latest version is always at <url
116url="http://samba.org/[.....]"> but there is probably a much
117nearer <url url="../MIRRORS" name="mirror site"> which you should use
118instead.
119
120<item> <url url="Samba-Server-FAQ.html"> is the best starting point for
121information about server-side issues. Includes configuration tips and
122pointers for Samba on particular operating systems (with 40 to choose
123from...)
124
125<item> <url url="Samba-Client-FAQ.html"> is the best starting point for
126information about client-side issues, includes a list of all clients
127that are known to work with Samba.
128
129<item> <url url="samba-man-index.html" name="manual pages"> contains
130descriptions of and links to all the Samba manual pages, in Unix man and
131postscript format.
132
133<item> <url url="samba-txt-index.html"> has descriptions of and links to
134a large number of text files have been contributed to samba covering
135many topics. These are gradually being absorbed into the FAQs and HOWTOs
136but in the meantime you might find helpful answers here.
137
138<item> 
139
140</itemize>
141
142<sect> General Information<p><label id="general_info">
143
144All about Samba - what it is, how to get it, related sources of
145information, how to understand the numbering scheme, pizza
146details.
147
148<sect1> What is Samba?<p><label id="introduction">
149
150Samba is a suite of programs which work together to allow clients to
151access to a server's filespace and printers via the SMB (Server Message
152Block) and CIFS (Common Internet Filesystem) protocols. Initially
153written for Unix, Samba now also runs on Netware, OS/2, VMS, StratOS and
154Amigas. Ports to BeOS and other operating systems are underway. Samba
155gives the capability for these operating systems to behave much like a
156LAN Server, Windows NT Server or Pathworks machine, only with added
157functionality and flexibility designed to make life easier for
158administrators. 
159
160This means that using Samba you can share a server's disks and printers
161to many sorts of network clients, including Lan Manager, Windows for
162Workgroups, Windows NT, Linux, OS/2, and AIX. There is also a generic
163client program supplied as part of the Samba suite which gives a user on
164the server an ftp-like interface to access filespace and printers on any
165other SMB/CIFS servers.
166
167SMB has been implemented over many protocols, including XNS, NBT, IPX,
168NetBEUI and TCP/IP. Samba only uses TCP/IP. This is not likely to change
169although there have been some requests for NetBEUI support.
170
171Many users report that compared to other SMB implementations Samba is
172more stable, faster, and compatible with more clients. Administrators of
173some large installations say that Samba is the only SMB server available
174which will scale to many tens of thousands of users without crashing.
175The easy way to test these claims is to download it and try it for
176yourself!
177
178The suite is supplied with full source code under the <url
179url="../COPYING" name="GNU Public License">. The GPL means that you can
180use Samba for whatever purpose you wish (including changing the source
181or selling it for money) but under all circumstances the source code
182must be made freely available. A copy of the GPL must always be included
183in any copy of the package.
184
185The primary creator of the Samba suite is Andrew Tridgell. Later
186versions incorporate much effort by many net.helpers. The man pages
187and this FAQ were originally written by Karl Auer.
188
189<sect1> What is the current version of Samba?<p><label id="current_version">
190
191At time of writing, the current version was 1.9.17. If you want to be
192sure check the bottom of the change-log file. <url url="ftp://samba.org/pub/samba/alpha/change-log">
193
194For more information see <ref id="version_nums" name="What do the version numbers mean?">
195
196<sect1> Where can I get it? <p><label id="WhereFrom">
197
198The Samba suite is available via anonymous ftp from samba.org and
199many <url url="../MIRRORS" name="mirror"> sites. You will get much
200faster performance if you use a mirror site. The latest and greatest
201versions of the suite are in the directory:
202
203/pub/samba/
204
205Development (read "alpha") versions, which are NOT necessarily stable
206and which do NOT necessarily have accurate documentation, are available
207in the directory:
208
209/pub/samba/alpha
210
211Note that binaries are NOT included in any of the above. Samba is
212distributed ONLY in source form, though binaries may be available from
213other sites. Most Linux distributions, for example, do contain Samba
214binaries for that platform. The VMS, OS/2, Netware and Amiga and other
215ports typically have binaries made available.
216
217A special case is vendor-provided binary packages. Samba binaries and
218default configuration files are put into packages for a specific
219operating system. RedHat Linux and Sun Solaris (Sparc and x86) is
220already included, and others such as OS/2 may follow. All packages are
221in the directory:
222
223/pub/samba/Binary_Packages/"OS_Vendor"
224
225<sect1>What do the version numbers mean?<p><label id="version_nums">
226
227It is not recommended that you run a version of Samba with the word
228"alpha" in its name unless you know what you are doing and are willing
229to do some debugging. Many, many people just get the latest
230recommended stable release version and are happy. If you are brave, by
231all means take the plunge and help with the testing and development -
232but don't install it on your departmental server. Samba is typically
233very stable and safe, and this is mostly due to the policy of many
234public releases.
235
236How the scheme works:
237
238<enum>
239
240<item>When major changes are made the version number is increased. For
241example, the transition from 1.9.16 to 1.9.17. However, this version
242number will not appear immediately and people should continue to use
2431.9.15 for production systems (see next point.)
244
245<item>Just after major changes are made the software is considered
246unstable, and a series of alpha releases are distributed, for example
2471.9.16alpha1. These are for testing by those who know what they are
248doing.  The "alpha" in the filename will hopefully scare off those who
249are just looking for the latest version to install.
250
251<item>When Andrew thinks that the alphas have stabilised to the point
252where he would recommend new users install it, he renames it to the
253same version number without the alpha, for example 1.9.17.
254
255<item>Inevitably bugs are found in the "stable" releases and minor patch
256levels are released which give us the pXX series, for example 1.9.17p2.
257
258</enum>
259
260So the progression goes:
261
262<verb>
263		1.9.16p10	(production)
264		1.9.16p11	(production)
265		1.9.17alpha1	(test sites only)
266		  :
267		1.9.17alpha20	(test sites only)
268		1.9.17		(production)
269		1.9.17p1	(production)
270</verb>
271
272The above system means that whenever someone looks at the samba ftp
273site they will be able to grab the highest numbered release without an
274alpha in the name and be sure of getting the current recommended
275version.
276
277<sect1> Where can I go for further information?<p><label id="more">
278
279There are a number of places to look for more information on Samba,
280including:
281
282<itemize>
283
284<item>Two mailing lists devoted to discussion of Samba-related matters.
285See below for subscription information.
286
287<item>The newsgroup comp.protocols.smb, which has a great deal of
288discussion about Samba. 
289
290<item>The WWW site 'SAMBA Web Pages' at <url
291url="http://samba.org/samba/"> includes:
292
293  <itemize>
294    <item>Links to man pages and documentation, including this FAQ
295    <item>A comprehensive survey of Samba users
296    <item>A searchable hypertext archive of the Samba mailing list
297    <item>Links to Samba source code, binaries, and mirrors of both
298    <item>This FAQ and the rest in its family
299  </itemize>
300
301</itemize>
302
303<sect1>How do I subscribe to the Samba Mailing Lists?<p><label id="mailinglist">
304
305Send email to <htmlurl url="mailto:listproc@samba.org"
306name="listproc@samba.org">. Make sure the subject line is blank,
307and include the following two lines in the body of the message:
308
309<tscreen><verb>
310subscribe samba Firstname Lastname
311subscribe samba-announce Firstname Lastname
312</verb></tscreen>
313
314Obviously you should substitute YOUR first name for "Firstname" and
315YOUR last name for "Lastname"! Try not to send any signature, it
316sometimes confuses the list processor.
317
318The samba list is a digest list - every eight hours or so it sends a
319single message containing all the messages that have been received by
320the list since the last time and sends a copy of this message to all
321subscribers. There are thousands of people on this list.
322
323If you stop being interested in Samba, please send another email to
324<htmlurl url="mailto:listproc@samba.org" name="listproc@samba.org">. Make sure the subject line is blank, and
325include the following two lines in the body of the message:
326
327<tscreen><verb>
328unsubscribe samba
329unsubscribe samba-announce
330</verb></tscreen>
331
332The <bf>From:</bf> line in your message <em>MUST</em> be the same
333address you used when you subscribed.
334
335<sect1> Something's gone wrong - what should I do?<p><label id="wrong">
336
337<bf>[#] *** IMPORTANT! *** [#]</bf>
338<p>
339
340DO NOT post messages on mailing lists or in newsgroups until you have
341carried out the first three steps given here!
342
343<enum> <item> See if there are any likely looking entries in this FAQ!
344If you have just installed Samba, have you run through the checklist in
345<url url="ftp://samba.org/pub/samba/DIAGNOSIS.txt"
346name="DIAGNOSIS.txt">? It can save you a lot of time and effort.
347DIAGNOSIS.txt can also be found in the docs directory of the Samba
348distribution.
349
350<item> Read the man pages for smbd, nmbd and smb.conf, looking for
351topics that relate to what you are trying to do.
352
353<item> If there is no obvious solution to hand, try to get a look at
354the log files for smbd and/or nmbd for the period during which you
355were having problems. You may need to reconfigure the servers to
356provide more extensive debugging information - usually level 2 or
357level 3 provide ample debugging info. Inspect these logs closely,
358looking particularly for the string "Error:".
359
360<item> If you need urgent help and are willing to pay for it see 
361<ref id="PaidSupport" name="Paid Support">.
362
363</enum>
364
365If you still haven't got anywhere, ask the mailing list or newsgroup. In
366general nobody minds answering questions provided you have followed the
367preceding steps. It might be a good idea to scan the archives of the
368mailing list, which are available through the Samba web site described
369in the previous section. When you post be sure to include a good
370description of your environment and your problem.
371
372If you successfully solve a problem, please mail the FAQ maintainer a
373succinct description of the symptom, the problem and the solution, so
374that an explanation can be incorporated into the next version.
375
376<sect1> How do I submit patches or bug reports?<p>
377
378If you make changes to the source code, <em>please</em> submit these patches
379so that everyone else gets the benefit of your work. This is one of
380the most important aspects to the maintainence of Samba. Send all
381patches to <htmlurl url="mailto:samba@samba.org" name="samba@samba.org">. Do not send patches to Andrew Tridgell or any
382other individual, they may be lost if you do.
383
384Patch format
385------------
386
387If you are sending a patch to fix a problem then please don't just use
388standard diff format. As an example, samba received this patch from
389someone:
390
391382a
392#endif
393..
394381a
395#if !defined(NEWS61)
396
397How are we supposed to work out what this does and where it goes? These
398sort of patches only work if we both have identical files in the first
399place. The Samba sources are constantly changing at the hands of multiple
400developers, so it doesn't work.
401
402Please use either context diffs or (even better) unified diffs. You
403get these using "diff -c4" or "diff -u". If you don't have a diff that
404can generate these then please send manualy commented patches to I
405know what is being changed and where. Most patches are applied by hand so
406the info must be clear.
407
408This is a basic guideline that will assist us with assessing your problem
409more efficiently :
410
411Machine Arch:
412Machine OS:
413OS Version:
414Kernel:
415
416Compiler:
417Libc Version:
418
419Samba Version:
420
421Network Layout (description):
422
423What else is on machine (services, etc):
424
425Some extras :
426
427<itemize>
428
429<item> what you did and what happened
430
431<item> relevant parts of a debugging output file with debuglevel higher.
432  If you can't find the relevant parts, please ask before mailing
433  huge files.
434
435<item> anything else you think is useful to trace down the bug
436
437</itemize>
438
439<sect1> What if I have an URGENT message for the developers?<p>
440
441If you have spotted something very serious and believe that it is
442important to contact the developers quickly send a message to
443samba-urgent@samba.org. This will be processed more quickly than
444mail to samba. Please think carefully before using this address. An
445example of its use might be to report a security hole.
446
447Examples of things <em>not</em> to send to samba-urgent include problems
448getting Samba to work at all and bugs that cannot potentially cause damage.
449
450<sect1> What if I need paid-for support?<p><label id=PaidSupport>
451
452Samba has a large network of consultants who provide Samba support on a
453commercial basis. The list is included in the package in <url
454url="../Support.txt">, and the latest version will always be on the main
455samba ftp site. Any company in the world can request that the samba team
456include their details in Support.txt so we can give no guarantee of
457their services.
458
459<sect1> Pizza supply details<p><label id="pizza">
460Those who have registered in the Samba survey as "Pizza Factory" will
461already know this, but the rest may need some help. Andrew doesn't ask
462for payment, but he does appreciate it when people give him
463pizza. This calls for a little organisation when the pizza donor is
464twenty thousand kilometres away, but it has been done.
465
466<enum>
467<item> Ring up your local branch of an international pizza chain
468and see if they honour their vouchers internationally. Pizza Hut do,
469which is how the entire Canberra Linux Users Group got to eat pizza
470one night, courtesy of someone in the US.
471
472<item>Ring up a local pizza shop in Canberra and quote a credit
473card number for a certain amount, and tell them that Andrew will be
474collecting it (don't forget to tell him.) One kind soul from Germany
475did this.
476
477<item>Purchase a pizza voucher from your local pizza shop that has
478no international affiliations and send it to Andrew. It is completely
479useless but he can hang it on the wall next to the one he already has
480from Germany :-)
481
482<item>Air freight him a pizza with your favourite regional
483flavours. It will probably get stuck in customs or torn apart by
484hungry sniffer dogs but it will have been a noble gesture.
485
486</enum>
487
488<sect>About the CIFS and SMB Protocols<p><label id="CifsSmb">
489
490<sect1> What is the Server Message Block (SMB) Protocol?<p>
491SMB is a filesharing protocol that has had several maintainers and
492contributors over the years including Xerox, 3Com and most recently
493Microsoft. Names for this protocol include LAN Manager and Microsoft 
494Networking. Parts of the specification has been made public at several 
495versions including in an X/Open document, as listed at 
496<url url="ftp://ftp.microsoft.com/developr/drg/CIFS/">. No specification
497releases were made between 1992 and 1996, and during that period
498Microsoft became the SMB implementor with the largest market share.
499Microsoft developed the specification further for its products but for
500various reasons connected with developer's workload rather than market
501strategy did not make the changes public. This culminated with the 
502"Windows NT 0.12" version released with NT 3.5 in 1995 which had significant 
503improvements and bugs. Because Microsoft client systems are so popular,
504it is fair to say that what Microsoft with Windows affects all suppliers
505of SMB server products.
506
507From 1994 Andrew Tridgell began doing some serious work on his 
508Smbserver (now Samba) product and with some helpers started to 
509implement more and more of these protocols. Samba began to take 
510a significant share of the SMB server market.
511
512<sect1> What is the Common Internet Filesystem (CIFS)?<p>
513The initial pressure for Microsoft to document their current SMB
514implementation came from the Samba team, who kept coming across things
515on the wire that Microsoft either didn't know about or hadn't documented
516anywhere (even in the sourcecode to Windows NT.) Then Sun Microsystems
517came out with their WebNFS initiative, designed to replace FTP for file
518transfers on the Internet. There are many drawbacks to WebNFS (including
519its scope - it aims to replace HTTP as well!) but the concept was
520attractive. FTP is not very clever, and why should it be harder to get
521files from across the world than across the room? 
522
523Some hasty revisions were made and an Internet Draft for the Common
524Internet Filesystem (CIFS) was released. Note that CIFS is not an
525Internet standard and is a very long way from becoming one, BUT the
526protocol specification is in the public domain and ongoing discussions
527concerning the spec take place on a public mailing list according to the
528rules of the Internet Engineering Task Force. For more information and
529pointers see <url url="http://samba.org/cifs/">
530
531The following is taken from <url url="http://www.microsoft.com/intdev/cifs/">
532
533<verb>
534    CIFS defines a standard remote file system access protocol for use
535    over the Internet, enabling groups of users to work together and
536    share documents across the Internet or within their corporate
537    intranets. CIFS is an open, cross-platform technology based on the
538    native file-sharing protocols built into Microsoft� Windows� and
539    other popular PC operating systems, and supported on dozens of
540    other platforms, including UNIX�. With CIFS, millions of computer
541    users can open and share remote files on the Internet without having
542    to install new software or change the way they work."
543</verb>
544
545If you consider CIFS as a backwardsly-compatible refinement of SMB that
546will work reasonably efficiently over the Internet you won't be too far
547wrong.
548
549The net effect is that Microsoft is now documenting large parts of their
550Windows NT fileserver protocols. The security concepts embodied in
551Windows NT are part of the specification, which is why Samba
552documentation often talks in terms of Windows NT. However there is no
553reason why a site shouldn't conduct all its file and printer sharing
554with CIFS and yet have no Microsoft products at all.
555
556<sect1> What is Browsing? <p>
557The term "Browsing" causes a lot of confusion. It is the part of the
558SMB/CIFS protocol which allows for resource discovery. For example, in
559the Windows NT Explorer it is possible to see a "Network Neighbourhood"
560of computers in the same SMB workgroup. Clicking on the name of one of 
561these machines brings up a list of file and printer resources for
562connecting to. In this way you can cruise the network, seeing what
563things are available. How this scales to the Internet is a subject for
564debate. Look at the CIFS list archives to see what the experts think.
565
566<sect>Designing A SMB and CIFS Network<p>
567
568The big issues for installing any network of LAN or WAN file and print
569servers are 
570
571<itemize> 
572
573<item>How and where usernames, passwords and other security information
574is stored 
575
576<item>What method can be used for locating the resources that users have
577permission to use 
578
579<item>What protocols the clients can converse with
580
581</itemize> 
582
583If you buy Netware, Windows NT or just about any other LAN fileserver
584product you are expected to lock yourself into the product's preferred
585answers to these questions. This tendancy is restrictive and often very
586expensive for a site where there is only one kind of client or server,
587and for sites with a mixture of operating systems it often makes it
588impossible to share resources between some sets of users.
589
590The Samba philosophy is to make things as easy as possible for
591administators, which means allowing as many combinations of clients,
592servers, operating systems and protocols as possible.
593
594<sect1>Workgroups, Domains, Authentication and Browsing<p>
595
596From the point of view of networking implementation, Domains and
597Workgroups are <em>exactly</em> the same, except for the client logon
598sequence. Some kind of distributed authentication database is associated
599with a domain (there are quite a few choices) and this adds so much
600flexibility that many people think of a domain as a completely different
601entity to a workgroup. From Samba's point of view a client connecting to
602a service presents an authentication token, and it if it is valid they
603have access. Samba does not care what mechanism was used to generate
604that token in the first place.
605
606The SMB client logging on to a domain has an expectation that every other
607server in the domain should accept the same authentication information.
608However the network browsing functionality of domains and workgroups is
609identical and is explained in <url url="../BROWSING.txt">.
610
611There are some implementation differences: Windows 95 can be a member of
612both a workgroup and a domain, but Windows NT cannot. Windows 95 also
613has the concept of an "alternative workgroup". Samba can only be a
614member of a single workgroup or domain, although this is due to change
615with a future version when nmbd will be split into two daemons, one for
616WINS and the other for browsing (<url url="../NetBIOS.txt"> explains
617what WINS is.)
618
619<sect2> Defining the Terms<p><label id="BrowseAndDomainDefs">
620
621<descrip>
622
623<tag/Workgroup/ means a collection of machines that maintain a common
624browsing database containing information about their shared resources.
625They do not necessarily have any security information in common (if they
626do, it gets called a Domain.) The browsing database is dynamic, modified
627as servers come and go on the network and as resources are added or
628deleted. The term "browsing" refers to a user accessing the database via
629whatever interface the client provides, eg the OS/2 Workplace Shell or
630Windows 95 Explorer. SMB servers agree between themselves as to which
631ones will maintain the browsing database. Workgroups can be anywhere on
632a connected TCP/IP network, including on different subnets or even on
633the Interet. This is a very tricky part of SMB to implement.
634
635<tag/Master Browsers/ are machines which holds the master browsing
636database for a workgroup or domain. There are two kinds of Master Browser:
637
638<itemize>
639
640<item> Domain Master Browser, which holds the master browsing
641information for an entire domain, which may well cross multiple TCP/IP
642subnets.
643
644<item> Local Master Browser, which holds the master browsing database
645for a particular subnet and communicates with the Domain Master Browser
646to get information on other subnets.
647
648</itemize>
649
650Subnets are differentiated because browsing is based on broadcasts, and
651broadcasts do not pass through routers. Subnets are not routed: while it
652is possible to have more than one subnet on a single network segment
653this is regarded as very bad practice.
654
655Master Browsers (both Domain and Local) are elected dynamically
656according to an algorithm which is supposed to take into account the
657machine's ability to sustain the browsing load. Samba can be configured
658to always act as a master browser, ie it always wins elections under all
659circumstances, even against systems such as a Windows NT Primary Domain
660Controller which themselves expect to win. 
661
662There are also Backup Browsers which are promoted to Master Browsers in
663the event of a Master Browser disappearing from the network.
664
665Alternative terms include confusing variations such as "Browse Master",
666and "Master Browser" which we are trying to eliminate from the Samba
667documentation. 
668
669<tag/Domain Controller/ is a term which comes from the Microsoft and IBM
670etc implementation of the LAN Manager protocols. It is tied to
671authentication. There are other ways of doing domain authentication, but
672the Windows NT method has a large market share. The general issues are
673discussed in <url url="../DOMAIN.txt"> and a Windows NT-specific
674discussion is in <url url="../DOMAIN_CONTROL.txt">.
675
676</descrip>
677
678<sect2>Sharelevel (Workgroup) Security Services<p><label id="ShareModeSecurity">
679
680With the Samba setting "security = SHARE", all shared resources
681information about what password is associated with them but only hints
682as to what usernames might be valid (the hint can be 'all users', in
683which case any username will work. This is usually a bad idea, but
684reflects both the initial implementations of SMB in the mid-80s and
685its reincarnation with Windows for Workgroups in 1992. The idea behind
686workgroup security was that small independant groups of people could
687share information on an ad-hoc basis without there being an
688authentication infrastructure present or requiring them to do more than
689fill in a dialogue box.
690
691<sect2>Authentication Domain Mode Services<p><label id="DomainModeSecurity">
692
693With the Samba settings "security = USER" or "security = SERVER"
694accesses to all resources are checked for username/password pair matches
695in a more rigorous manner. To the client, this has the effect of
696emulating a Microsoft Domain. The client is not concerned whether or not
697Samba looks up a Windows NT SAM or does it in some other way.
698
699<sect1>Authentication Schemes<p>
700
701In the simple case authentication information is stored on a single
702server and the user types a password on connecting for the first time.
703However client operating systems often require a password before they
704can be used at all, and in addition users usually want access to more
705than one server. Asking users to remember many different passwords in
706different contexts just does not work. Some kind of distributed
707authentication database is needed. It must cope with password changes
708and provide for assigning groups of users the same level of access
709permissions. This is why Samba installations often choose to implement a
710Domain model straight away.
711
712Authentication decisions are some of the biggest in designing a network.
713Are you going to use a scheme native to the client operating system,
714native to the server operating system, or newly installed on both? A
715list of options relevant to Samba (ie that make sense in the context of
716the SMB protocol) follows. Any experiences with other setups would be
717appreciated. [refer to server FAQ for "passwd chat" passwd program 
718password server etc etc...]
719
720<sect2>NIS<p>
721
722For Windows 95, Windows for Workgroups and most other clients Samba can
723be a domain controller and share the password database via NIS
724transparently. Windows NT is different. 
725<url url="http://www.dcs.qmw.ac.uk/~williams" name="Free NIS NT client">
726
727<sect2>Kerberos<p>
728
729Kerberos for US users only:
730<url url="http://www.cygnus.com/product/unifying-security.html"
731name="Kerberos overview">
732<url url="http://www.cygnus.com/product/kerbnet-download.html"
733name="Download Kerberos">
734
735<sect2>FTP<p>
736
737Other NT w/s logon hack via NT
738
739<sect2>Default Server Method<p>
740
741<sect2>Client-side Database Only<p>
742
743<sect1>Post-Authentication: Netlogon, Logon Scripts, Profiles<p>
744
745See <url url="../DOMAIN.txt">
746
747<sect>Cross-Protocol File Sharing<p>
748
749Samba is an important tool for...
750
751It is possible to...
752
753File protocol gateways...
754
755"Setting up a Linux File Server" http://vetrec.mit.edu/people/narf/linux.html
756
757Two free implementations of Appletalk for Unix are Netatalk, <url
758url="http://www.umich.edu/~rsug/netatalk/">, and CAP, <url
759url="http://www.cs.mu.oz.au/appletalk/atalk.html">. What Samba offers MS
760Windows users, these packages offer to Macs. For more info on these
761packages, Samba, and Linux (and other UNIX-based systems) see <url
762url="http://www.eats.com/linux_mac_win.html"> 3.5) Sniffing your nework
763
764
765<sect>Miscellaneous<p><label id="miscellaneous">
766<sect1>Is Samba Year 2000 compliant?<p><label id="Year2000Compliant">
767The CIFS protocol that Samba implements
768negotiates times in various formats, all of which
769are able to cope with dates beyond 2000.
770
771</article>
772