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<table class="head">
<tr>
<td class="head-ltitle">RESCUE(8)</td>
<td class="head-vol">System Manager's Manual</td>
<td class="head-rtitle">RESCUE(8)</td>
</tr>
</table>
<div class="manual-text">
<section class="Sh">
<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1>
<p class="Pp"><code class="Nm">rescue</code> — <span class="Nd">rescue
utilities in <span class="Pa">/rescue</span></span></p>
</section>
<section class="Sh">
<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1>
<p class="Pp">The <span class="Pa">/rescue</span> directory contains a
collection of common utilities intended for use in recovering a badly
damaged system. With the transition to a dynamically-linked root beginning
with <span class="Ux">FreeBSD 5.2</span>, there is a real possibility that
the standard tools in <span class="Pa">/bin</span> and
<span class="Pa">/sbin</span> may become non-functional due to a failed
upgrade or a disk error. The tools in <span class="Pa">/rescue</span> are
statically linked and should therefore be more resistant to damage. However,
being statically linked, the tools in <span class="Pa">/rescue</span> are
also less functional than the standard utilities. In particular, they do not
have full use of the locale, <a class="Xr">pam(3)</a>, and nsswitch
libraries.</p>
<p class="Pp">If your system fails to boot, and it shows a prompt similar
to:</p>
<p class="Pp"></p>
<div class="Bd Bd-indent"><code class="Li">Enter full pathname of shell or
RETURN for /bin/sh: </code></div>
<p class="Pp">the first thing to try running is the standard shell,
<span class="Pa">/bin/sh</span>. If that fails, try running
<span class="Pa">/rescue/sh</span>, which is the
<code class="Nm">rescue</code> shell. To repair the system, the root
partition must first be remounted read-write. This can be done with the
following <a class="Xr">mount(8)</a> command:</p>
<p class="Pp"></p>
<div class="Bd Bd-indent"><code class="Li">/rescue/mount -uw /</code></div>
<p class="Pp">The next step is to double-check the contents of
<span class="Pa">/bin</span>, <span class="Pa">/sbin</span>, and
<span class="Pa">/usr/lib</span>, possibly mounting a
<span class="Ux">FreeBSD</span> rescue or “live file system”
CD-ROM and copying files from there. Once it is possible to successfully run
<span class="Pa">/bin/sh</span>, <span class="Pa">/bin/ls</span>, and other
standard utilities, try rebooting back into the standard system.</p>
<p class="Pp">The <span class="Pa">/rescue</span> tools are compiled using
<a class="Xr">crunchgen(1)</a>, which makes them considerably more compact
than the standard utilities. To build a <span class="Ux">FreeBSD</span>
system where space is critical, <span class="Pa">/rescue</span> can be used
as a replacement for the standard <span class="Pa">/bin</span> and
<span class="Pa">/sbin</span> directories; simply change
<span class="Pa">/bin</span> and <span class="Pa">/sbin</span> to be
symbolic links pointing to <span class="Pa">/rescue</span>. Since
<span class="Pa">/rescue</span> is statically linked, it should also be
possible to dispense with much of <span class="Pa">/usr/lib</span> in such
an environment.</p>
<p class="Pp">In contrast to its predecessor <span class="Pa">/stand</span>,
<span class="Pa">/rescue</span> is updated during normal
<span class="Ux">FreeBSD</span> source and binary upgrades.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h1>
<dl class="Bl-tag Bl-compact">
<dt><span class="Pa">/rescue</span></dt>
<dd>Root of the <code class="Nm">rescue</code> hierarchy.</dd>
</dl>
</section>
<section class="Sh">
<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE
ALSO</a></h1>
<p class="Pp"><a class="Xr">crunchgen(1)</a>, <a class="Xr">crash(8)</a></p>
</section>
<section class="Sh">
<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1>
<p class="Pp">The <code class="Nm">rescue</code> utilities first appeared in
<span class="Ux">FreeBSD 5.2</span>.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1>
<p class="Pp">The <code class="Nm">rescue</code> system was written by
<span class="An">Tim Kientzle</span>
<<a class="Mt" href="mailto:kientzle@FreeBSD.org">kientzle@FreeBSD.org</a>>,
based on ideas taken from <span class="Ux">NetBSD</span>. This manual page
was written by <span class="An">Simon L. Nielsen</span>
<<a class="Mt" href="mailto:simon@FreeBSD.org">simon@FreeBSD.org</a>>,
based on text by <span class="An">Tim Kientzle</span>
<<a class="Mt" href="mailto:kientzle@FreeBSD.org">kientzle@FreeBSD.org</a>>.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1>
<p class="Pp">Most of the <code class="Nm">rescue</code> tools work even in a
fairly crippled system. The most egregious exception is the
<code class="Nm">rescue</code> version of <a class="Xr">vi(1)</a>, which
currently requires that <span class="Pa">/usr</span> be mounted so that it
can access the <a class="Xr">termcap(5)</a> files. Hopefully, a failsafe
<a class="Xr">termcap(3)</a> entry will eventually be added into the
<a class="Xr">ncurses(3)</a> library, so that
<span class="Pa">/rescue/vi</span> can be used even in a system where
<span class="Pa">/usr</span> cannot immediately be mounted. In the meantime,
the <code class="Nm">rescue</code> version of the <a class="Xr">ed(1)</a>
editor can be used from <span class="Pa">/rescue/ed</span> if you need to
edit files, but cannot mount <span class="Pa">/usr</span>.</p>
</section>
</div>
<table class="foot">
<tr>
<td class="foot-date">June 30, 2022</td>
<td class="foot-os">FreeBSD 15.0</td>
</tr>
</table>
|
