update-leap.html revision 362716
1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ --> 4<head> 5<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 6<title>update-leap User’s Manual</title> 7 8<meta name="description" content="update-leap User’s Manual"> 9<meta name="keywords" content="update-leap User’s Manual"> 10<meta name="resource-type" content="document"> 11<meta name="distribution" content="global"> 12<meta name="Generator" content="makeinfo"> 13<link href="#Top" rel="start" title="Top"> 14<link href="dir.html#Top" rel="up" title="(dir)"> 15<style type="text/css"> 16<!-- 17a.summary-letter {text-decoration: none} 18blockquote.indentedblock {margin-right: 0em} 19blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} 20blockquote.smallquotation {font-size: smaller} 21div.display {margin-left: 3.2em} 22div.example {margin-left: 3.2em} 23div.lisp {margin-left: 3.2em} 24div.smalldisplay {margin-left: 3.2em} 25div.smallexample {margin-left: 3.2em} 26div.smalllisp {margin-left: 3.2em} 27kbd {font-style: oblique} 28pre.display {font-family: inherit} 29pre.format {font-family: inherit} 30pre.menu-comment {font-family: serif} 31pre.menu-preformatted {font-family: serif} 32pre.smalldisplay {font-family: inherit; font-size: smaller} 33pre.smallexample {font-size: smaller} 34pre.smallformat {font-family: inherit; font-size: smaller} 35pre.smalllisp {font-size: smaller} 36span.nolinebreak {white-space: nowrap} 37span.roman {font-family: initial; font-weight: normal} 38span.sansserif {font-family: sans-serif; font-weight: normal} 39ul.no-bullet {list-style: none} 40--> 41</style> 42 43 44</head> 45 46<body lang="en"> 47<h1 class="settitle" align="center">update-leap User’s Manual</h1> 48 49 50 51 52 53<a name="Top"></a> 54<div class="header"> 55<p> 56Previous: <a href="dir.html#Top" accesskey="p" rel="prev">(dir)</a>, Up: <a href="dir.html#Top" accesskey="u" rel="up">(dir)</a> </p> 57</div> 58<h1 class="node-heading">Top</h1> 59 60<p>This document describes the use of the NTP Project’s <code>update-leap</code> program. 61</p> 62<p>This document applies to version 4.2.8p15 of <code>update-leap</code>. 63</p> 64<a name="SEC_Overview"></a> 65<h2 class="shortcontents-heading">Short Table of Contents</h2> 66 67<div class="shortcontents"> 68<li><a name="stoc-Invoking-update_002dleap" href="#toc-Invoking-update_002dleap">1 Invoking update-leap</a></li> 69 70</div> 71 72 73<table class="menu" border="0" cellspacing="0"> 74<tr><td align="left" valign="top">• update-leap Description:</td><td> </td><td align="left" valign="top">Description 75</td></tr> 76<tr><td align="left" valign="top">• <a href="#update_002dleap-Invocation" accesskey="2">update-leap Invocation</a>:</td><td> </td><td align="left" valign="top">Invoking update-leap 77</td></tr> 78</table> 79 80<hr> 81<a name="update_002dleap-Invocation"></a> 82<div class="header"> 83<p> 84Up: <a href="#Top" accesskey="u" rel="up">Top</a> </p> 85</div> 86<a name="Invoking-update_002dleap"></a> 87<h3 class="section">1 Invoking update-leap</h3> 88<a name="index-update_002dleap"></a> 89<a name="index-leap_002dseconds-file-manager_002fupdater"></a> 90 91 92 93<p><code>update-leap</code> 94will validate the file currently on the local system 95and if necessary, updates leap-second definition file. 96</p> 97<p>Ordinarily, the file is found using the "leapfile" directive in 98<code>ntp.conf(5)</code>. 99However, an alternate location can be specified on the command line. 100</p> 101<p>If the file does not exist, is not valid, has expired, or is expiring soon, 102a new copy will be downloaded. If the new copy validates, it is installed and 103NTP is (optionally) restarted. 104</p> 105<p>If the current file is acceptable, no download or restart occurs. 106</p> 107<p>-c can also be used to invoke another script to perform administrative 108functions, e.g. to copy the file to other local systems. 109.PP 110This can be run as a cron job. As the file is rarely updated, and leap 111seconds are announced at least one month in advance (usually longer), it 112need not be run more frequently than about once every three weeks. 113.PP 114For cron-friendly behavior, define CRONJOB=1 in the crontab. 115.PP 116This script depends on$REQUIREDCMDS 117</p> 118<p>This section was generated by <strong>AutoGen</strong>, 119using the <code>agtexi-cmd</code> template and the option descriptions for the <code>update-leap</code> program. 120</p> 121<table class="menu" border="0" cellspacing="0"> 122<tr><td align="left" valign="top">• <a href="#update_002dleap-usage" accesskey="1">update-leap usage</a>:</td><td> </td><td align="left" valign="top">update-leap help/usage (<samp>--help</samp>) 123</td></tr> 124<tr><td align="left" valign="top">• <a href="#update_002dleap-source_002durl" accesskey="2">update-leap source-url</a>:</td><td> </td><td align="left" valign="top">source-url option (-s) 125</td></tr> 126<tr><td align="left" valign="top">• <a href="#update_002dleap-ipv4" accesskey="3">update-leap ipv4</a>:</td><td> </td><td align="left" valign="top">ipv4 option (-4) 127</td></tr> 128<tr><td align="left" valign="top">• <a href="#update_002dleap-destination" accesskey="4">update-leap destination</a>:</td><td> </td><td align="left" valign="top">destination option (-d) 129</td></tr> 130<tr><td align="left" valign="top">• <a href="#update_002dleap-expiration" accesskey="5">update-leap expiration</a>:</td><td> </td><td align="left" valign="top">expiration option (-e) 131</td></tr> 132<tr><td align="left" valign="top">• <a href="#update_002dleap-ntp_002dconf_002dfile" accesskey="6">update-leap ntp-conf-file</a>:</td><td> </td><td align="left" valign="top">ntp-conf-file option (-f) 133</td></tr> 134<tr><td align="left" valign="top">• <a href="#update_002dleap-force_002dupdate" accesskey="7">update-leap force-update</a>:</td><td> </td><td align="left" valign="top">force-update option (-F) 135</td></tr> 136<tr><td align="left" valign="top">• <a href="#update_002dleap-exit-status" accesskey="8">update-leap exit status</a>:</td><td> </td><td align="left" valign="top">exit status 137</td></tr> 138<tr><td align="left" valign="top">• <a href="#update_002dleap-Usage" accesskey="9">update-leap Usage</a>:</td><td> </td><td align="left" valign="top">Usage 139</td></tr> 140<tr><td align="left" valign="top">• <a href="#update_002dleap-Authors">update-leap Authors</a>:</td><td> </td><td align="left" valign="top">Authors 141</td></tr> 142</table> 143 144<hr> 145<a name="update_002dleap-usage"></a> 146<div class="header"> 147<p> 148Next: <a href="#update_002dleap-source_002durl" accesskey="n" rel="next">update-leap source-url</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 149</div> 150<a name="update_002dleap-help_002fusage-_0028_002d_002dhelp_0029"></a> 151<h4 class="subsection">1.1 update-leap help/usage (<samp>--help</samp>)</h4> 152<a name="index-update_002dleap-help"></a> 153 154<p>This is the automatically generated usage text for update-leap. 155</p> 156<p>The text printed is the same whether selected with the <code>help</code> option 157(<samp>--help</samp>) or the <code>more-help</code> option (<samp>--more-help</samp>). <code>more-help</code> will print 158the usage text by passing it through a pager program. 159<code>more-help</code> is disabled on platforms without a working 160<code>fork(2)</code> function. The <code>PAGER</code> environment variable is 161used to select the program, defaulting to <samp>more</samp>. Both will exit 162with a status code of 0. 163</p> 164<div class="example"> 165<pre class="example"> 166 167Usage: update-leap [options] 168 169Verifies and if necessary, updates leap-second definition file 170 171All arguments are optional: Default (or current value) shown: 172 -C Absolute path to CA Cert (see SSL/TLS Considerations) 173 -D Path to a CAdir (see SSL/TLS Considerations) 174 -e Specify how long (in days) before expiration the file is to be 175 refreshed. Note that larger values imply more frequent refreshes. 176 60 177 -F Force update even if current file is OK and not close to expiring. 178 -f Absolute path ntp.conf file (default /etc/ntp.conf) 179 /etc/ntp.conf 180 -h show help 181 -i Specify number of minutes between retries 182 10 183 -L Absolute path to leapfile on the local system 184 (overrides value in ntp.conf) 185 -l Specify the syslog(3) facility for logging 186 LOG_USER 187 -q Only report errors (cannot be used with -v) 188 -r Specify number of attempts to retrieve file 189 6 190 -s Send output to syslog(3) - implied if STDOUT has no tty or redirected 191 -t Send output to terminal - implied if STDOUT attached to terminal 192 -u Specify the URL of the master copy to download 193 https://www.ietf.org/timezones/data/leap-seconds.list 194 -v Verbose - show debug messages (cannot be used with -q) 195 196The following options are not (yet) implemented in the perl version: 197 -4 Use only IPv4 198 -6 Use only IPv6 199 -c Command to restart NTP after installing a new file 200 <none> - ntpd checks file daily 201 -p 4|6 202 Prefer IPv4 or IPv6 (as specified) addresses, but use either 203 204update-leap will validate the file currently on the local system. 205 206Ordinarily, the leapfile is found using the 'leapfile' directive in 207/etc/ntp.conf. However, an alternate location can be specified on the 208command line with the -L flag. 209 210If the leapfile does not exist, is not valid, has expired, or is 211expiring soon, a new copy will be downloaded. If the new copy is 212valid, it is installed. 213 214If the current file is acceptable, no download or restart occurs. 215 216This can be run as a cron job. As the file is rarely updated, and 217leap seconds are announced at least one month in advance (usually 218longer), it need not be run more frequently than about once every 219three weeks. 220 221SSL/TLS Considerations 222----------------------- 223The perl modules can usually locate the CA certificate used to verify 224the peer's identity. 225 226On BSDs, the default is typically the file /etc/ssl/certs.pem. On 227Linux, the location is typically a path to a CAdir - a directory of 228symlinks named according to a hash of the certificates' subject names. 229 230The -C or -D options are available to pass in a location if no CA cert 231is found in the default location. 232 233External Dependencies 234--------------------- 235The following perl modules are required: 236HTTP::Tiny - version >= 0.056 237IO::Socket::SSL - version >= 1.56 238NET::SSLeay - version >= 1.49 239 240Version: 1.004 241</pre></div> 242 243<hr> 244<a name="update_002dleap-source_002durl"></a> 245<div class="header"> 246<p> 247Next: <a href="#update_002dleap-ipv4" accesskey="n" rel="next">update-leap ipv4</a>, Previous: <a href="#update_002dleap-usage" accesskey="p" rel="prev">update-leap usage</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 248</div> 249<a name="source_002durl-option-_0028_002ds_0029"></a> 250<h4 class="subsection">1.2 source-url option (-s)</h4> 251<a name="index-update_002dleap_002dsource_002durl"></a> 252 253<p>This is the “the url of the master copy of the leapseconds file” option. 254This option takes a string argument. 255Specify the URL of the master copy to download 256$LEAPSRC 257</p><hr> 258<a name="update_002dleap-ipv4"></a> 259<div class="header"> 260<p> 261Next: <a href="#update_002dleap-destination" accesskey="n" rel="next">update-leap destination</a>, Previous: <a href="#update_002dleap-source_002durl" accesskey="p" rel="prev">update-leap source-url</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 262</div> 263<a name="ipv4-option-_0028_002d4_0029"></a> 264<h4 class="subsection">1.3 ipv4 option (-4)</h4> 265<a name="index-update_002dleap_002dipv4"></a> 266 267<p>This is the “use only ipv4 addresses for dns name resolution” option. 268</p> 269<p>This option has some usage constraints. It: 270</p><ul> 271<li> must not appear in combination with any of the following options: 272ipv6. 273</li></ul> 274 275<p>Force DNS resolution of following host names on the command line 276 to the IPv4 namespace. 277 _EndOfDoc_; 278; 279</p> 280<p>flag = 281 name = ipv6; 282 flags-cant = ipv4, prefer; 283 value = 6; 284 descrip = "Use only IPv6 addresses for DNS name resolution"; 285 doc = <<- _EndOfDoc_ 286 Force DNS resolution of following host names on the command line 287 to the IPv6 namespace. 288 _EndOfDoc_; 289; 290</p> 291<p>flag = 292 name = prefer; 293 flags-cant = ipv4, ipv6; 294 value = p; 295 arg-type = keyword; 296 keyword = 4, 6; 297 descrip = ’Prefer IPv4 or IPv6 (as specified) addresses, but use either’; 298 doc = <<- _EndOfDoc_ 299Prefer IPv4 or IPv6 (as specified) addresses, but use either. 300</p><hr> 301<a name="update_002dleap-destination"></a> 302<div class="header"> 303<p> 304Next: <a href="#update_002dleap-expiration" accesskey="n" rel="next">update-leap expiration</a>, Previous: <a href="#update_002dleap-ipv4" accesskey="p" rel="prev">update-leap ipv4</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 305</div> 306<a name="destination-option-_0028_002dd_0029"></a> 307<h4 class="subsection">1.4 destination option (-d)</h4> 308<a name="index-update_002dleap_002ddestination"></a> 309 310<p>This is the “filename on the local system” option. 311This option takes a string argument <samp>float</samp>. 312The name to use to store the leapfile on the local system. 313$LEAPFILE 314</p><hr> 315<a name="update_002dleap-expiration"></a> 316<div class="header"> 317<p> 318Next: <a href="#update_002dleap-ntp_002dconf_002dfile" accesskey="n" rel="next">update-leap ntp-conf-file</a>, Previous: <a href="#update_002dleap-destination" accesskey="p" rel="prev">update-leap destination</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 319</div> 320<a name="expiration-option-_0028_002de_0029"></a> 321<h4 class="subsection">1.5 expiration option (-e)</h4> 322<a name="index-update_002dleap_002dexpiration"></a> 323 324<p>This is the “refresh the leapfile this long before it expires” option. 325This option takes a string argument. 326Specify how long before expiration the file is to be refreshed 327Units are required, e.g. "-e 60 days" Note that larger values 328imply more frequent refreshes. 329"$PREFETCH" 330</p><hr> 331<a name="update_002dleap-ntp_002dconf_002dfile"></a> 332<div class="header"> 333<p> 334Next: <a href="#update_002dleap-force_002dupdate" accesskey="n" rel="next">update-leap force-update</a>, Previous: <a href="#update_002dleap-expiration" accesskey="p" rel="prev">update-leap expiration</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 335</div> 336<a name="ntp_002dconf_002dfile-option-_0028_002df_0029"></a> 337<h4 class="subsection">1.6 ntp-conf-file option (-f)</h4> 338<a name="index-update_002dleap_002dntp_002dconf_002dfile"></a> 339 340<p>This is the “location of the ntp.conf file” option. 341This option takes a string argument. 342Specify location of ntp.conf (used to make sure leapfile directive is 343present and to default leapfile) 344/etc/ntp.conf 345</p><hr> 346<a name="update_002dleap-force_002dupdate"></a> 347<div class="header"> 348<p> 349Next: <a href="#update_002dleap-exit-status" accesskey="n" rel="next">update-leap exit status</a>, Previous: <a href="#update_002dleap-ntp_002dconf_002dfile" accesskey="p" rel="prev">update-leap ntp-conf-file</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 350</div> 351<a name="force_002dupdate-option-_0028_002dF_0029"></a> 352<h4 class="subsection">1.7 force-update option (-F)</h4> 353<a name="index-update_002dleap_002dforce_002dupdate"></a> 354 355<p>This is the “force update of the leapfile” option. 356Force update even if current file is OK and not close to expiring. 357</p><hr> 358<a name="update_002dleap-exit-status"></a> 359<div class="header"> 360<p> 361Next: <a href="#update_002dleap-Usage" accesskey="n" rel="next">update-leap Usage</a>, Previous: <a href="#update_002dleap-force_002dupdate" accesskey="p" rel="prev">update-leap force-update</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 362</div> 363<a name="update_002dleap-exit-status-1"></a> 364<h4 class="subsection">1.8 update-leap exit status</h4> 365 366<p>One of the following exit values will be returned: 367</p><dl compact="compact"> 368<dt>‘<samp>0 (EXIT_SUCCESS)</samp>’</dt> 369<dd><p>Successful program execution. 370</p></dd> 371<dt>‘<samp>1 (EXIT_FAILURE)</samp>’</dt> 372<dd><p>The operation failed or the command syntax was not valid. 373</p></dd> 374</dl> 375<hr> 376<a name="update_002dleap-Usage"></a> 377<div class="header"> 378<p> 379Next: <a href="#update_002dleap-Authors" accesskey="n" rel="next">update-leap Authors</a>, Previous: <a href="#update_002dleap-exit-status" accesskey="p" rel="prev">update-leap exit status</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 380</div> 381<a name="update_002dleap-Usage-1"></a> 382<h4 class="subsection">1.9 update-leap Usage</h4> 383<hr> 384<a name="update_002dleap-Authors"></a> 385<div class="header"> 386<p> 387Previous: <a href="#update_002dleap-Usage" accesskey="p" rel="prev">update-leap Usage</a>, Up: <a href="#update_002dleap-Invocation" accesskey="u" rel="up">update-leap Invocation</a> </p> 388</div> 389<a name="update_002dleap-Authors-1"></a> 390<h4 class="subsection">1.10 update-leap Authors</h4> 391<hr> 392 393 394 395</body> 396</html> 397