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diff --git a/share/man/man8/rescue.8 b/share/man/man8/rescue.8 new file mode 100644 index 000000000000..685827f3d598 --- /dev/null +++ b/share/man/man8/rescue.8 @@ -0,0 +1,184 @@ +.\" Copyright (c) 2003 Tim Kientzle <kientzle@acm.org> +.\" Copyright (c) 2003 Simon L. Nielsen <simon@FreeBSD.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd July 23, 2003 +.Os +.Dt RESCUE 8 +.Sh NAME +.Nm rescue +.Nd rescue utilities in +.Pa /rescue +.Sh DESCRIPTION +The +.Pa /rescue +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 +.Fx 5.2 , +there is a real possibility that the standard tools in +.Pa /bin +and +.Pa /sbin +may become non-functional due to a failed upgrade or a disk error. +The tools in +.Pa /rescue +are statically linked and should therefore be more resistant to +damage. +However, being statically linked, the tools in +.Pa /rescue +are also less functional than the standard utilities. +In particular, they do not have full use of the locale, +.Xr pam 3 , +and nsswitch libraries. +.Pp +If your system fails to boot, and it shows a prompt similar to: +.Pp +.Dl "Enter full pathname of shell or RETURN for /bin/sh: " +.Pp +the first thing to try running is the standard shell, +.Pa /bin/sh . +If that fails, try running +.Pa /rescue/sh , +which is the +.Nm +shell. +To repair the system, the root partition must first be remounted +read-write. +This can be done with the following +.Xr mount 8 +command: +.Pp +.Dl "/rescue/mount -uw /" +.Pp +The next step is to double-check the contents of +.Pa /bin , /sbin , +and +.Pa /usr/lib , +possibly mounting a +.Fx +rescue or +.Dq "live file system" +CD-ROM (e.g., +.Li disc2 +of the officially released +.Fx +ISO images) and copying files from there. +Once it is possible to successfully run +.Pa /bin/sh , /bin/ls , +and other standard utilities, try rebooting back into the standard +system. +.Pp +The +.Pa /rescue +tools are compiled using +.Xr crunchgen 1 , +which makes them considerably more compact than the standard +utilities. +To build a +.Fx +system where space is critical, +.Pa /rescue +can be used as a replacement for the standard +.Pa /bin +and +.Pa /sbin +directories; simply change +.Pa /bin +and +.Pa /sbin +to be symbolic links pointing to +.Pa /rescue . +Since +.Pa /rescue +is statically linked, it should also be possible to dispense with much +of +.Pa /usr/lib +in such an environment. +.Pp +In contrast to its predecessor +.Pa /stand , +.Pa /rescue +is updated during normal +.Fx +source and binary upgrades. +.Sh FILES +.Bl -tag -width ".Pa /rescue" -compact +.It Pa /rescue +Root of the +.Nm +hierarchy. +.El +.Sh SEE ALSO +.Xr crunchgen 1 , +.Xr crash 8 +.Sh HISTORY +The +.Nm +utilities first appeared in +.Fx 5.2 . +.Sh AUTHORS +.An -nosplit +The +.Nm +system was written by +.An Tim Kientzle Aq kientzle@FreeBSD.org , +based on ideas taken from +.Nx . +This manual page was written by +.An Simon L. Nielsen Aq simon@FreeBSD.org , +based on text by +.An Tim Kientzle Aq kientzle@FreeBSD.org . +.Sh BUGS +Most of the +.Nm +tools work even in a fairly crippled system. +The most egregious exception is the +.Nm +version of +.Xr vi 1 , +which currently requires that +.Pa /usr +be mounted so that it can access the +.Xr termcap 5 +files. +Hopefully, a failsafe +.Xr termcap 3 +entry will eventually be added into the +.Xr ncurses 3 +library, so that +.Pa /rescue/vi +can be used even in a system where +.Pa /usr +cannot immediately be mounted. +In the meantime, the +.Nm +version of the +.Xr ed 1 +editor can be used from +.Pa /rescue/ed +if you need to edit files, but cannot mount +.Pa /usr . |