diff options
Diffstat (limited to 'doc/html/man/expire_backups.html')
| -rw-r--r-- | doc/html/man/expire_backups.html | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/doc/html/man/expire_backups.html b/doc/html/man/expire_backups.html new file mode 100644 index 0000000..e50daa6 --- /dev/null +++ b/doc/html/man/expire_backups.html @@ -0,0 +1,242 @@ + + +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + + +<html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> + + <title>The expire_backups command — S3QL 1.0.1 documentation</title> + + <link rel="stylesheet" href="../_static/sphinxdoc.css" type="text/css" /> + <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> + + <script type="text/javascript"> + var DOCUMENTATION_OPTIONS = { + URL_ROOT: '../', + VERSION: '1.0.1', + COLLAPSE_INDEX: false, + FILE_SUFFIX: '.html', + HAS_SOURCE: true + }; + </script> + <script type="text/javascript" src="../_static/jquery.js"></script> + <script type="text/javascript" src="../_static/underscore.js"></script> + <script type="text/javascript" src="../_static/doctools.js"></script> + <link rel="author" title="About these documents" href="../about.html" /> + <link rel="top" title="S3QL 1.0.1 documentation" href="../index.html" /> + <link rel="up" title="Manpages" href="index.html" /> + <link rel="next" title="Further Resources / Getting Help" href="../resources.html" /> + <link rel="prev" title="The pcp command" href="pcp.html" /> + </head> + <body> + <div class="related"> + <h3>Navigation</h3> + <ul> + <li class="right" style="margin-right: 10px"> + <a href="../resources.html" title="Further Resources / Getting Help" + accesskey="N">next</a></li> + <li class="right" > + <a href="pcp.html" title="The pcp command" + accesskey="P">previous</a> |</li> + <li><a href="../index.html">S3QL 1.0.1 documentation</a> »</li> + <li><a href="index.html" accesskey="U">Manpages</a> »</li> + </ul> + </div> + <div class="sphinxsidebar"> + <div class="sphinxsidebarwrapper"> + <h3><a href="../index.html">Table Of Contents</a></h3> + <ul class="current"> +<li class="toctree-l1"><a class="reference internal" href="../about.html">About S3QL</a></li> +<li class="toctree-l1"><a class="reference internal" href="../installation.html">Installation</a></li> +<li class="toctree-l1"><a class="reference internal" href="../backends.html">Storage Backends</a></li> +<li class="toctree-l1"><a class="reference internal" href="../mkfs.html">File System Creation</a></li> +<li class="toctree-l1"><a class="reference internal" href="../adm.html">Managing Buckets</a></li> +<li class="toctree-l1"><a class="reference internal" href="../mount.html">Mounting</a></li> +<li class="toctree-l1"><a class="reference internal" href="../special.html">Advanced S3QL Features</a></li> +<li class="toctree-l1"><a class="reference internal" href="../umount.html">Unmounting</a></li> +<li class="toctree-l1"><a class="reference internal" href="../fsck.html">Checking for Errors</a></li> +<li class="toctree-l1"><a class="reference internal" href="../contrib.html">Contributed Programs</a></li> +<li class="toctree-l1"><a class="reference internal" href="../tips.html">Tips & Tricks</a></li> +<li class="toctree-l1"><a class="reference internal" href="../issues.html">Known Issues</a></li> +<li class="toctree-l1 current"><a class="reference internal" href="index.html">Manpages</a><ul class="current"> +<li class="toctree-l2"><a class="reference internal" href="mkfs.html">The <strong class="program">mkfs.s3ql</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="adm.html">The <strong class="program">s3qladm</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="mount.html">The <strong class="program">mount.s3ql</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="stat.html">The <strong class="program">s3qlstat</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="ctrl.html">The <strong class="program">s3qlctrl</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="cp.html">The <strong class="program">s3qlcp</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="rm.html">The <strong class="program">s3qlrm</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="lock.html">The <strong class="program">s3qllock</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="umount.html">The <strong class="program">umount.s3ql</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="fsck.html">The <strong class="program">fsck.s3ql</strong> command</a></li> +<li class="toctree-l2"><a class="reference internal" href="pcp.html">The <strong class="program">pcp</strong> command</a></li> +<li class="toctree-l2 current"><a class="current reference internal" href="">The <strong class="program">expire_backups</strong> command</a></li> +</ul> +</li> +<li class="toctree-l1"><a class="reference internal" href="../resources.html">Further Resources / Getting Help</a></li> +</ul> + + + <div id="searchbox" style="display: none"> + <h3>Quick search</h3> + <form class="search" action="../search.html" method="get"> + <input type="text" name="q" size="18" /> + <input type="submit" value="Go" /> + <input type="hidden" name="check_keywords" value="yes" /> + <input type="hidden" name="area" value="default" /> + </form> + <p class="searchtip" style="font-size: 90%"> + Enter search terms. + </p> + </div> + <script type="text/javascript">$('#searchbox').show(0);</script> + </div> + </div> + + <div class="document"> + <div class="documentwrapper"> + <div class="bodywrapper"> + <div class="body"> + + <div class="section" id="the-expire-backups-command"> +<h1>The <strong class="program">expire_backups</strong> command<a class="headerlink" href="#the-expire-backups-command" title="Permalink to this headline">¶</a></h1> +<div class="section" id="synopsis"> +<h2>Synopsis<a class="headerlink" href="#synopsis" title="Permalink to this headline">¶</a></h2> +<div class="highlight-commandline"><div class="highlight"><pre><span class="l">expire_backups </span><span class="ge">[options]</span><span class="l"> </span><span class="nv"><age></span><span class="l"> </span><span class="ge">[<age> ...]</span><span class="l"></span> +</pre></div> +</div> +</div> +<div class="section" id="description"> +<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2> +<p>The <strong class="command">expire_backups</strong> command intelligently remove old backups that are no +longer needed.</p> +<p>To define what backups you want to keep for how long, you define a +number of <em>age ranges</em>. <strong class="program">expire_backups</strong> ensures that you +will have at least one backup in each age range at all times. It will +keep exactly as many backups as are required for that and delete any +backups that become redundant.</p> +<p>Age ranges are specified by giving a list of range boundaries in terms +of backup cycles. Every time you create a new backup, the existing +backups age by one cycle.</p> +<p>Example: when <strong class="program">expire_backups</strong> is called with the age range +definition <tt class="docutils literal"><span class="pre">1</span> <span class="pre">3</span> <span class="pre">7</span> <span class="pre">14</span> <span class="pre">31</span></tt>, it will guarantee that you always have the +following backups available:</p> +<ol class="arabic simple"> +<li>A backup that is 0 to 1 cycles old (i.e, the most recent backup)</li> +<li>A backup that is 1 to 3 cycles old</li> +<li>A backup that is 3 to 7 cycles old</li> +<li>A backup that is 7 to 14 cycles old</li> +<li>A backup that is 14 to 31 cycles old</li> +</ol> +<div class="admonition note"> +<p class="first admonition-title">Note</p> +<p class="last">If you do backups in fixed intervals, then one cycle will be +equivalent to the backup interval. The advantage of specifying the +age ranges in terms of backup cycles rather than days or weeks is +that it allows you to gracefully handle irregular backup intervals. +Imagine that for some reason you do not turn on your computer for +one month. Now all your backups are at least a month old, and if you +had specified the above backup strategy in terms of absolute ages, +they would all be deleted! Specifying age ranges in terms of backup +cycles avoids these sort of problems.</p> +</div> +<p><strong class="program">expire_backups</strong> usage is simple. It requires backups to have +names of the forms <tt class="docutils literal"><span class="pre">year-month-day_hour:minute:seconds</span></tt> +(<tt class="docutils literal"><span class="pre">YYYY-MM-DD_HH:mm:ss</span></tt>) and works on all backups in the current +directory. So for the above backup strategy, the correct invocation +would be:</p> +<div class="highlight-commandline"><div class="highlight"><pre><span class="l">expire_backups.py 1 3 7 14 31</span> +</pre></div> +</div> +<p>When storing your backups on an S3QL file system, you probably want to +specify the <tt class="docutils literal"><span class="pre">--use-s3qlrm</span></tt> option as well. This tells +<strong class="program">expire_backups</strong> to use the <a class="reference internal" href="../special.html#s3qlrm"><em>s3qlrm</em></a> command to +delete directories.</p> +<p><strong class="program">expire_backups</strong> uses a “state file” to keep track which +backups are how many cycles old (since this cannot be inferred from +the dates contained in the directory names). The standard name for +this state file is <tt class="file docutils literal"><span class="pre">.expire_backups.dat</span></tt>. If this file gets +damaged or deleted, <strong class="program">expire_backups</strong> no longer knows the ages +of the backups and refuses to work. In this case you can use the +<tt class="cmdopt docutils literal"><span class="pre">--reconstruct-state</span></tt> option to try to reconstruct the state +from the backup dates. However, the accuracy of this reconstruction +depends strongly on how rigorous you have been with making backups (it +is only completely correct if the time between subsequent backups has +always been exactly the same), so it’s generally a good idea not to +tamper with the state file.</p> +</div> +<div class="section" id="options"> +<h2>Options<a class="headerlink" href="#options" title="Permalink to this headline">¶</a></h2> +<p>The <strong class="command">expire_backups</strong> command accepts the following options:</p> +<blockquote> +<div><table class="docutils option-list" frame="void" rules="none"> +<col class="option" /> +<col class="description" /> +<tbody valign="top"> +<tr><td class="option-group"> +<kbd><span class="option">--quiet</span></kbd></td> +<td>be really quiet</td></tr> +<tr><td class="option-group"> +<kbd><span class="option">--debug</span></kbd></td> +<td>activate debugging output</td></tr> +<tr><td class="option-group"> +<kbd><span class="option">--version</span></kbd></td> +<td>just print program version and exit</td></tr> +<tr><td class="option-group"> +<kbd><span class="option">--state <var><file></var></span></kbd></td> +<td>File to save state information in (default: +”.expire_backups.dat”)</td></tr> +<tr><td class="option-group"> +<kbd><span class="option">-n</span></kbd></td> +<td>Dry run. Just show which backups would be deleted.</td></tr> +<tr><td class="option-group" colspan="2"> +<kbd><span class="option">--reconstruct-state</span></kbd></td> +</tr> +<tr><td> </td><td>Try to reconstruct a missing state file from backup +dates.</td></tr> +<tr><td class="option-group"> +<kbd><span class="option">--use-s3qlrm</span></kbd></td> +<td>Use <tt class=" docutils literal"><span class="pre">s3qlrm</span></tt> command to delete backups.</td></tr> +</tbody> +</table> +</div></blockquote> +</div> +<div class="section" id="exit-status"> +<h2>Exit Status<a class="headerlink" href="#exit-status" title="Permalink to this headline">¶</a></h2> +<p><strong class="command">expire_backups</strong> returns exit code 0 if the operation succeeded and 1 if some +error occured.</p> +</div> +<div class="section" id="see-also"> +<h2>See Also<a class="headerlink" href="#see-also" title="Permalink to this headline">¶</a></h2> +<p><strong class="command">expire_backups</strong> is shipped as part of S3QL, <a class="reference external" href="http://code.google.com/p/s3ql/">http://code.google.com/p/s3ql/</a>.</p> +</div> +</div> + + + </div> + </div> + </div> + <div class="clearer"></div> + </div> + <div class="related"> + <h3>Navigation</h3> + <ul> + <li class="right" style="margin-right: 10px"> + <a href="../resources.html" title="Further Resources / Getting Help" + >next</a></li> + <li class="right" > + <a href="pcp.html" title="The pcp command" + >previous</a> |</li> + <li><a href="../index.html">S3QL 1.0.1 documentation</a> »</li> + <li><a href="index.html" >Manpages</a> »</li> + </ul> + </div> + <div class="footer"> + © Copyright 2008-2011, Nikolaus Rath. + Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 1.1pre. + </div> + </body> +</html>
\ No newline at end of file |