update-leap.html revision 281348
1281348Scy<html lang="en"> 2281348Scy<head> 3281348Scy<title>update-leap User's Manual</title> 4281348Scy<meta http-equiv="Content-Type" content="text/html"> 5281348Scy<meta name="description" content="update-leap User's Manual"> 6281348Scy<meta name="generator" content="makeinfo 4.7"> 7281348Scy<link title="Top" rel="top" href="#Top"> 8281348Scy<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 9281348Scy<meta http-equiv="Content-Style-Type" content="text/css"> 10281348Scy<style type="text/css"><!-- 11281348Scy pre.display { font-family:inherit } 12281348Scy pre.format { font-family:inherit } 13281348Scy pre.smalldisplay { font-family:inherit; font-size:smaller } 14281348Scy pre.smallformat { font-family:inherit; font-size:smaller } 15281348Scy pre.smallexample { font-size:smaller } 16281348Scy pre.smalllisp { font-size:smaller } 17281348Scy span.sc { font-variant:small-caps } 18281348Scy span.roman { font-family: serif; font-weight: normal; } 19281348Scy--></style> 20281348Scy</head> 21281348Scy<body> 22281348Scy<h1 class="settitle">update-leap User's Manual</h1> 23281348Scy<div class="node"> 24281348Scy<p><hr> 25281348Scy<a name="Top"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-Description">update-leap Description</a>, 26281348ScyPrevious: <a rel="previous" accesskey="p" href="#dir">(dir)</a>, 27281348ScyUp: <a rel="up" accesskey="u" href="#dir">(dir)</a> 28281348Scy<br> 29281348Scy</div> 30281348Scy 31281348Scy <p>This document describes the use of the NTP Project's <code>update-leap</code> program. 32281348Scy 33281348Scy <p>This document applies to version 4.2.8p2 of <code>update-leap</code>. 34281348Scy 35281348Scy<div class="shortcontents"> 36281348Scy<h2>Short Contents</h2> 37281348Scy<ul> 38281348Scy</ul> 39281348Scy</div> 40281348Scy 41281348Scy<ul class="menu"> 42281348Scy<li><a accesskey="1" href="#update_002dleap-Description">update-leap Description</a>: Description 43281348Scy<li><a accesskey="2" href="#update_002dleap-Invocation">update-leap Invocation</a>: Invoking update-leap 44281348Scy</ul> 45281348Scy 46281348Scy<div class="node"> 47281348Scy<p><hr> 48281348Scy<a name="update_002dleap-Invocation"></a> 49281348Scy<br> 50281348Scy</div> 51281348Scy 52281348Scy<h3 class="section">0.1 Invoking update-leap</h3> 53281348Scy 54281348Scy<p><a name="index-update_002dleap-1"></a><a name="index-leap_002dseconds-file-manager_002fupdater-2"></a> 55281348Scy 56281348Scy <p><code>update-leap</code> 57281348Scywill validate the file currently on the local system 58281348Scyand if necessary, updates leap-second definition file. 59281348Scy 60281348Scy <p>Ordinarily, the file is found using the "leapfile" directive in 61281348Scy<code>ntp.conf(5)</code>. 62281348ScyHowever, an alternate location can be specified on the command line. 63281348Scy 64281348Scy <p>If the file does not exist, is not valid, has expired, or is expiring soon, 65281348Scya new copy will be downloaded. If the new copy validates, it is installed and 66281348ScyNTP is (optionally) restarted. 67281348Scy 68281348Scy <p>If the current file is acceptable, no download or restart occurs. 69281348Scy 70281348Scy <p>-c can also be used to invoke another script to perform administrative 71281348Scyfunctions, e.g. to copy the file to other local systems. 72281348Scy.PP 73281348ScyThis can be run as a cron job. As the file is rarely updated, and leap 74281348Scyseconds are announced at least one month in advance (usually longer), it 75281348Scyneed not be run more frequently than about once every three weeks. 76281348Scy.PP 77281348ScyFor cron-friendly behavior, define CRONJOB=1 in the crontab. 78281348Scy.PP 79281348ScyThis script depends on$REQUIREDCMDS 80281348Scy 81281348Scy <p>This section was generated by <strong>AutoGen</strong>, 82281348Scyusing the <code>agtexi-cmd</code> template and the option descriptions for the <code>update-leap</code> program. 83281348Scy 84281348Scy<ul class="menu"> 85281348Scy<li><a accesskey="1" href="#update_002dleap-usage">update-leap usage</a>: update-leap help/usage (<span class="option">--help</span>) 86281348Scy<li><a accesskey="2" href="#update_002dleap-source_002durl">update-leap source-url</a>: source-url option (-s) 87281348Scy<li><a accesskey="3" href="#update_002dleap-ipv4">update-leap ipv4</a>: ipv4 option (-4) 88281348Scy<li><a accesskey="4" href="#update_002dleap-destination">update-leap destination</a>: destination option (-d) 89281348Scy<li><a accesskey="5" href="#update_002dleap-expiration">update-leap expiration</a>: expiration option (-e) 90281348Scy<li><a accesskey="6" href="#update_002dleap-ntp_002dconf_002dfile">update-leap ntp-conf-file</a>: ntp-conf-file option (-f) 91281348Scy<li><a accesskey="7" href="#update_002dleap-force_002dupdate">update-leap force-update</a>: force-update option (-F) 92281348Scy<li><a accesskey="8" href="#update_002dleap-exit-status">update-leap exit status</a>: exit status 93281348Scy<li><a accesskey="9" href="#update_002dleap-Usage">update-leap Usage</a>: Usage 94281348Scy<li><a href="#update_002dleap-Authors">update-leap Authors</a>: Authors 95281348Scy</ul> 96281348Scy 97281348Scy<div class="node"> 98281348Scy<p><hr> 99281348Scy<a name="update_002dleap-usage"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-source_002durl">update-leap source-url</a>, 100281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 101281348Scy<br> 102281348Scy</div> 103281348Scy 104281348Scy<h4 class="subsection">0.1.1 update-leap help/usage (<span class="option">--help</span>)</h4> 105281348Scy 106281348Scy<p><a name="index-update_002dleap-help-3"></a> 107281348ScyThis is the automatically generated usage text for update-leap. 108281348Scy 109281348Scy <p>The text printed is the same whether selected with the <code>help</code> option 110281348Scy(<span class="option">--help</span>) or the <code>more-help</code> option (<span class="option">--more-help</span>). <code>more-help</code> will print 111281348Scythe usage text by passing it through a pager program. 112281348Scy<code>more-help</code> is disabled on platforms without a working 113281348Scy<code>fork(2)</code> function. The <code>PAGER</code> environment variable is 114281348Scyused to select the program, defaulting to <span class="file">more</span>. Both will exit 115281348Scywith a status code of 0. 116281348Scy 117281348Scy<pre class="example">/bin/bash: line 136: ./update-leap: Permission denied 118281348Scy</pre> 119281348Scy <div class="node"> 120281348Scy<p><hr> 121281348Scy<a name="update_002dleap-source_002durl"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-ipv4">update-leap ipv4</a>, 122281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-usage">update-leap usage</a>, 123281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 124281348Scy<br> 125281348Scy</div> 126281348Scy 127281348Scy<h4 class="subsection">0.1.2 source-url option (-s)</h4> 128281348Scy 129281348Scy<p><a name="index-update_002dleap_002dsource_002durl-4"></a> 130281348ScyThis is the “the url of the master copy of the leapseconds file” option. 131281348ScyThis option takes a string argument. 132281348ScySpecify the URL of the master copy to download 133281348Scy$LEAPSRC 134281348Scy<div class="node"> 135281348Scy<p><hr> 136281348Scy<a name="update_002dleap-ipv4"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-destination">update-leap destination</a>, 137281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-source_002durl">update-leap source-url</a>, 138281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 139281348Scy<br> 140281348Scy</div> 141281348Scy 142281348Scy<h4 class="subsection">0.1.3 ipv4 option (-4)</h4> 143281348Scy 144281348Scy<p><a name="index-update_002dleap_002dipv4-5"></a> 145281348ScyThis is the “use only ipv4 addresses for dns name resolution” option. 146281348Scy 147281348Scy<p class="noindent">This option has some usage constraints. It: 148281348Scy <ul> 149281348Scy<li>must not appear in combination with any of the following options: 150281348Scyipv6. 151281348Scy</ul> 152281348Scy 153281348Scy <p>Force DNS resolution of following host names on the command line 154281348Scy to the IPv4 namespace. 155281348Scy _EndOfDoc_; 156281348Scy; 157281348Scy 158281348Scy <p>flag = 159281348Scy name = ipv6; 160281348Scy flags-cant = ipv4, prefer; 161281348Scy value = 6; 162281348Scy descrip = "Use only IPv6 addresses for DNS name resolution"; 163281348Scy doc = <<- _EndOfDoc_ 164281348Scy Force DNS resolution of following host names on the command line 165281348Scy to the IPv6 namespace. 166281348Scy _EndOfDoc_; 167281348Scy; 168281348Scy 169281348Scy <p>flag = 170281348Scy name = prefer; 171281348Scy flags-cant = ipv4, ipv6; 172281348Scy value = p; 173281348Scy arg-type = keyword; 174281348Scy keyword = 4, 6; 175281348Scy descrip = 'Prefer IPv4 or IPv6 (as specified) addresses, but use either'; 176281348Scy doc = <<- _EndOfDoc_ 177281348ScyPrefer IPv4 or IPv6 (as specified) addresses, but use either. 178281348Scy<div class="node"> 179281348Scy<p><hr> 180281348Scy<a name="update_002dleap-destination"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-expiration">update-leap expiration</a>, 181281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-ipv4">update-leap ipv4</a>, 182281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 183281348Scy<br> 184281348Scy</div> 185281348Scy 186281348Scy<h4 class="subsection">0.1.4 destination option (-d)</h4> 187281348Scy 188281348Scy<p><a name="index-update_002dleap_002ddestination-6"></a> 189281348ScyThis is the “filename on the local system” option. 190281348ScyThis option takes a string argument <span class="file">float</span>. 191281348ScyThe name to use to store the leapfile on the local system. 192281348Scy$LEAPFILE 193281348Scy<div class="node"> 194281348Scy<p><hr> 195281348Scy<a name="update_002dleap-expiration"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-ntp_002dconf_002dfile">update-leap ntp-conf-file</a>, 196281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-destination">update-leap destination</a>, 197281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 198281348Scy<br> 199281348Scy</div> 200281348Scy 201281348Scy<h4 class="subsection">0.1.5 expiration option (-e)</h4> 202281348Scy 203281348Scy<p><a name="index-update_002dleap_002dexpiration-7"></a> 204281348ScyThis is the “refresh the leapfile this long before it expires” option. 205281348ScyThis option takes a string argument. 206281348ScySpecify how long before expiration the file is to be refreshed 207281348ScyUnits are required, e.g. "-e 60 days" Note that larger values 208281348Scyimply more frequent refreshes. 209281348Scy"$PREFETCH" 210281348Scy<div class="node"> 211281348Scy<p><hr> 212281348Scy<a name="update_002dleap-ntp_002dconf_002dfile"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-force_002dupdate">update-leap force-update</a>, 213281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-expiration">update-leap expiration</a>, 214281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 215281348Scy<br> 216281348Scy</div> 217281348Scy 218281348Scy<h4 class="subsection">0.1.6 ntp-conf-file option (-f)</h4> 219281348Scy 220281348Scy<p><a name="index-update_002dleap_002dntp_002dconf_002dfile-8"></a> 221281348ScyThis is the “location of the ntp.conf file” option. 222281348ScyThis option takes a string argument. 223281348ScySpecify location of ntp.conf (used to make sure leapfile directive is 224281348Scypresent and to default leapfile) 225281348Scy/etc/ntp.conf 226281348Scy<div class="node"> 227281348Scy<p><hr> 228281348Scy<a name="update_002dleap-force_002dupdate"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-exit-status">update-leap exit status</a>, 229281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-ntp_002dconf_002dfile">update-leap ntp-conf-file</a>, 230281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 231281348Scy<br> 232281348Scy</div> 233281348Scy 234281348Scy<h4 class="subsection">0.1.7 force-update option (-F)</h4> 235281348Scy 236281348Scy<p><a name="index-update_002dleap_002dforce_002dupdate-9"></a> 237281348ScyThis is the “force update of the leapfile” option. 238281348ScyForce update even if current file is OK and not close to expiring. 239281348Scy<div class="node"> 240281348Scy<p><hr> 241281348Scy<a name="update_002dleap-exit-status"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-Usage">update-leap Usage</a>, 242281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-force_002dupdate">update-leap force-update</a>, 243281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 244281348Scy<br> 245281348Scy</div> 246281348Scy 247281348Scy<h4 class="subsection">0.1.8 update-leap exit status</h4> 248281348Scy 249281348Scy<p>One of the following exit values will be returned: 250281348Scy <dl> 251281348Scy<dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution. 252281348Scy<br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid. 253281348Scy</dl> 254281348Scy <div class="node"> 255281348Scy<p><hr> 256281348Scy<a name="update_002dleap-Usage"></a>Next: <a rel="next" accesskey="n" href="#update_002dleap-Authors">update-leap Authors</a>, 257281348ScyPrevious: <a rel="previous" accesskey="p" href="#update_002dleap-exit-status">update-leap exit status</a>, 258281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 259281348Scy<br> 260281348Scy</div> 261281348Scy 262281348Scy<h4 class="subsection">0.1.9 update-leap Usage</h4> 263281348Scy 264281348Scy<div class="node"> 265281348Scy<p><hr> 266281348Scy<a name="update_002dleap-Authors"></a>Previous: <a rel="previous" accesskey="p" href="#update_002dleap-Usage">update-leap Usage</a>, 267281348ScyUp: <a rel="up" accesskey="u" href="#update_002dleap-Invocation">update-leap Invocation</a> 268281348Scy<br> 269281348Scy</div> 270281348Scy 271281348Scy<h4 class="subsection">0.1.10 update-leap Authors</h4> 272281348Scy 273281348Scy</body></html> 274281348Scy 275