virt-rescue [--options] -a disk.img [-a disk.img ...]
+ virt-rescue --suggest (-d domname | -a disk.img ...)
+
Old style:
virt-rescue [--options] domname
hand. There is an empty directory called C</sysroot> where you can
mount filesystems.
-In the example below, we list logical volumes, then choose one to
-mount under C</sysroot>:
+You can get virt-rescue to suggest mount commands for you by using the
+I<--suggest> option (in another terminal):
+
+ $ virt-rescue --suggest -d Fedora15
+ Inspecting the virtual machine or disk image ...
+
+ This disk contains one or more operating systems. You can use these
+ mount commands in virt-rescue (at the ><rescue> prompt) to mount the
+ filesystems.
+
+ # /dev/vg_f15x32/lv_root is the root of a linux operating system
+ # type: linux, distro: fedora, version: 15.0
+ # Fedora release 15 (Lovelock)
+
+ mount /dev/vg_f15x32/lv_root /sysroot/
+ mount /dev/vda1 /sysroot/boot
+ mount --bind /dev /sysroot/dev
+ mount --bind /dev/pts /sysroot/dev/pts
+ mount --bind /proc /sysroot/proc
+ mount --bind /sys /sysroot/sys
+
+Another way is to list the logical volumes (with L<lvs(8)>) and
+partitions (with L<parted(8)>) and mount them by hand:
><rescue> lvs
LV VG Attr LSize Origin Snap% Move Log Copy% Convert
- lv_root vg_f11x64 -wi-a- 8.83G
- lv_swap vg_f11x64 -wi-a- 992.00M
- ><rescue> mount /dev/vg_f11x64/lv_root /sysroot
+ lv_root vg_f15x32 -wi-a- 8.83G
+ lv_swap vg_f15x32 -wi-a- 992.00M
+ ><rescue> mount /dev/vg_f15x32/lv_root /sysroot
+ ><rescue> mount /dev/vda1 /sysroot/boot
><rescue> ls /sysroot
-If you don't know what filesystems are available on the virtual
-machine then you can use commands such as L<parted(8)> and L<lvs(8)>
-to find out.
+Another command to list available filesystems is
+L<virt-filesystems(1)>.
+
+To run commands in a Linux guest (for example, grub), you should
+chroot into the /sysroot directory first:
+
+ ><rescue> chroot /sysroot
=head2 NOTES
L<guestfish(1)> instead as it is more suitable for this purpose). You
can even use virt-rescue on things like SD cards.
+Virt-rescue does not require root. You only need to run it as root if
+you need root to open the disk image.
+
This tool is just designed for quick interactive hacking on a virtual
machine. For more structured access to a virtual machine disk image,
you should use L<guestfs(3)>. To get a structured shell that you can
=item B<--domain> guest
-Add all the disks from the named libvirt guest.
+Add all the disks from the named libvirt guest. Domain UUIDs can be
+used instead of names.
=item B<--format=raw|qcow2|..>
If you have untrusted raw-format guest disk images, you should use
this option to specify the disk format. This avoids a possible
-security problem with malicious guests (CVE-2010-3851). See also
-L</add-drive-opts>.
+security problem with malicious guests (CVE-2010-3851).
=item B<-m MB>
=item B<--network>
-Enable QEMU user networking in the guest.
+Enable QEMU user networking in the guest. See L</NETWORK>.
=item B<-r>
might be running, and is generally recommended in cases where you
don't need write access to the disk.
+See also L<guestfish(1)/OPENING DISKS FOR READ AND WRITE>.
+
=item B<--selinux>
Enable SELinux in the rescue appliance. You should read
L<guestfs(3)/SELINUX> before using this option.
+=item B<--smp> N
+
+Enable N E<ge> 2 virtual CPUs in the rescue appliance.
+
+=item B<--suggest>
+
+Inspect the disk image and suggest what mount commands should be used
+to mount the disks. You should use the I<--suggest> option in a
+second terminal, then paste the commands into another virt-rescue.
+
+This option implies I<--ro> and is safe to use even if the guest is up
+or if another virt-rescue is running.
+
=item B<-v>
=item B<--verbose>
Display version number and exit.
+=item B<-w>
+
+=item B<--rw>
+
+This changes the I<-a> and I<-d> options so that disks are
+added and mounts are done read-write.
+
+See L<guestfish(1)/OPENING DISKS FOR READ AND WRITE>.
+
=item B<-x>
Enable tracing of libguestfs API calls.
For compatibility the old style is still supported.
+=head1 NETWORK
+
+Adding the I<--network> option enables QEMU user networking
+in the rescue appliance. There are some differences between
+user networking and ordinary networking:
+
+=over 4
+
+=item ping does not work
+
+Because the ICMP ECHO_REQUEST protocol generally requires root in
+order to send the ping packets, and because virt-rescue must be able
+to run as non-root, QEMU user networking is not able to emulate the
+L<ping(8)> command. The ping command will appear to resolve addresses
+but will not be able to send or receive any packets. This does not
+mean that the network is not working.
+
+=item cannot receive connections
+
+QEMU user networking cannot receive incoming connections.
+
+=item making TCP connections
+
+The virt-rescue appliance needs to be small and so does not include
+many network tools. In particular there is no L<telnet(1)> command.
+You can make TCP connections from the shell using the magical
+C</dev/tcp/E<lt>hostnameE<gt>/E<lt>portE<gt>> syntax:
+
+ exec 3<>/dev/tcp/redhat.com/80
+ echo "GET /" >&3
+ cat <&3
+
+See L<bash(1)> for more details.
+
+=back
+
=head1 ENVIRONMENT VARIABLES
Several environment variables affect virt-rescue. See
quote or escape these characters on the command line. See the shell
manual page L<sh(1)> for details.
+=head1 FILES
+
+=over 4
+
+=item $HOME/.libguestfs-tools.rc
+
+=item /etc/libguestfs-tools.conf
+
+This configuration file controls the default read-only or read-write
+mode (I<--ro> or I<--rw>).
+
+See L<guestfish(1)/OPENING DISKS FOR READ AND WRITE>.
+
+=back
+
=head1 SEE ALSO
L<guestfs(3)>,
L<guestfish(1)>,
L<virt-cat(1)>,
L<virt-edit(1)>,
+L<virt-filesystems(1)>,
L<http://libguestfs.org/>.
=head1 AUTHOR
=head1 COPYRIGHT
-Copyright (C) 2009-2010 Red Hat Inc.
+Copyright (C) 2009-2011 Red Hat Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
git.annexia.org / libguestfs.git / blobdiff