=encoding utf8 =head1 NAME guestfish - the libguestfs filesystem interactive shell =head1 SYNOPSIS guestfish [--options] [commands] guestfish -i libvirt-domain guestfish -i disk-image(s) =head1 EXAMPLES =head2 From shell scripts Create a new C file in a guest: guestfish <<_EOF_ add disk.img run mount /dev/VolGroup00/LogVol00 / write_file /etc/motd "Hello users" 0 _EOF_ List the LVs in a guest: guestfish <<_EOF_ add disk.img run lvs _EOF_ =head2 On the command line List the LVM PVs in a guest image: guestfish add disk.img : run : pvs Remove C (in reality not such a great idea): guestfish --add disk.img \ --mount /dev/VolGroup00/LogVol00 \ --mount /dev/sda1:/boot \ rm /boot/grub/menu.lst =head2 As an interactive shell $ guestfish Welcome to guestfish, the libguestfs filesystem interactive shell for editing virtual machine filesystems. Type: 'help' for help with commands 'quit' to quit the shell > help =head2 As a script interpreter #!/usr/bin/guestfish -f alloc /tmp/output.img 10M run sfdisk /dev/sda 0 0 0 , mkfs ext2 /dev/sda1 =head2 Remote control eval `guestfish --listen` guestfish --remote cmd =head1 DESCRIPTION Guestfish is a shell and command-line tool for examining and modifying virtual machine filesystems. It uses libguestfs and exposes all of the functionality of the guestfs API, see L. =head1 OPTIONS =over 4 =item B<--help> Displays general help on options. =item B<-h> | B<--cmd-help> Lists all available guestfish commands. =item B<-h cmd> | B<--cmd-help cmd> Displays detailed help on a single command C. =item B<-a image> | B<--add image> Add a block device or virtual machine image to the shell. =item B<-D> | B<--no-dest-paths> Don't tab-complete paths on the guest filesystem. It is useful to be able to hit the tab key to complete paths on the guest filesystem, but this causes extra "hidden" guestfs calls to be made, so this option is here to allow this feature to be disabled. =item B<-f file> | B<--file file> Read commands from C. To write pure guestfish scripts, use: #!/usr/bin/guestfish -f =item B<-i> | B<--inspector> Run virt-inspector on the named libvirt domain or list of disk images. If virt-inspector is available and if it can identify the domain or disk images, then partitions will be mounted correctly at start-up. Typical usage is either: guestfish -i myguest (for an inactive libvirt domain called I), or: guestfish --ro -i myguest (for active domains, readonly), or specify the block device directly: guestfish -i /dev/Guests/MyGuest You cannot use I<-a>, I<-m>, I<--listen> or I<--remote> in conjunction with this option, and options other than I<--ro> might not behave correctly. See also: L. =item B<--listen> Fork into the background and listen for remote commands. See section I below. =item B<-m dev[:mountpoint]> | B<--mount dev[:mountpoint]> Mount the named partition or logical volume on the given mountpoint. If the mountpoint is omitted, it defaults to C. You have to mount something on C before most commands will work. If any C<-m> or C<--mount> options are given, the guest is automatically launched. =item B<-n> | B<--no-sync> Disable autosync. This is enabled by default. See the discussion of autosync in the L manpage. =item B<--remote[=pid]> Send remote commands to C<$GUESTFISH_PID> or C. See section I below. =item B<-r> | B<--ro> This changes the C<-m> option so that mounts are done read-only (see C in the L manpage). =item B<-v> | B<--verbose> Enable very verbose messages. This is particularly useful if you find a bug. =item B<-V> | B<--version> Display the guestfish / libguestfs version number and exit. =item B<-x> Echo each command before executing it. =back =head1 COMMANDS ON COMMAND LINE Any additional (non-option) arguments are treated as commands to execute. Commands to execute should be separated by a colon (C<:>), where the colon is a separate parameter. Thus: guestfish cmd [args...] : cmd [args...] : cmd [args...] ... If there are no additional arguments, then we enter a shell, either an interactive shell with a prompt (if the input is a terminal) or a non-interactive shell. In either command line mode or non-interactive shell, the first command that gives an error causes the whole shell to exit. In interactive mode (with a prompt) if a command fails, you can continue to enter commands. =head1 USING launch (OR run) As with L, you must first configure your guest by adding disks, then launch it, then mount any disks you need, and finally issue actions/commands. So the general order of the day is: =over 4 =item * add or -a/--add =item * launch (aka run) =item * mount or -m/--mount =item * any other commands =back C is a synonym for C. You must C (or C) your guest before mounting or performing any other commands. The only exception is that if the C<-m> or C<--mount> option was given, the guest is automatically run for you (simply because guestfish can't mount the disks you asked for without doing this). =head1 QUOTING You can quote ordinary parameters using either single or double quotes. For example: add "file with a space.img" rm '/file name' rm '/"' A few commands require a list of strings to be passed. For these, use a space-separated list, enclosed in quotes. For example: vgcreate VG "/dev/sda1 /dev/sdb1" =head1 WILDCARDS AND GLOBBING Neither guestfish nor the underlying guestfs API performs wildcard expansion (globbing) by default. So for example the following will not do what you expect: rm-rf /home/* Assuming you don't have a directory literally called C then the above command will return an error. To perform wildcard expansion, use the C command. glob rm-rf /home/* runs C on each path that matches (ie. potentially running the command many times), equivalent to: rm-rf /home/jim rm-rf /home/joe rm-rf /home/mary C only works on simple guest paths and not on device names. If you have several parameters, each containing a wildcard, then glob will perform a cartesian product. =head1 COMMENTS Any line which starts with a I<#> character is treated as a comment and ignored. The I<#> can optionally be preceeded by whitespace, but B by a command. For example: # this is a comment # this is a comment foo # NOT a comment Blank lines are also ignored. =head1 RUNNING COMMANDS LOCALLY Any line which starts with a I character is treated as a command sent to the local shell (C or whatever L uses). For example: !mkdir local tgz-out /remote local/remote-data.tar.gz will create a directory C on the host, and then export the contents of C on the mounted filesystem to C. (See C). =head1 PIPES Use CspaceE | command> to pipe the output of the first command (a guestfish command) to the second command (any host command). For example: cat /etc/passwd | awk -F: '$3 == 0 { print }' (where C is the guestfish cat command, but C is the host awk program). The above command would list all accounts in the guest filesystem which have UID 0, ie. root accounts including backdoors. Other examples: hexdump /bin/ls | head list-devices | tail -1 The space before the pipe symbol is required, any space after the pipe symbol is optional. Everything after the pipe symbol is just passed straight to the host shell, so it can contain redirections, globs and anything else that makes sense on the host side. To use a literal argument which begins with a pipe symbol, you have to quote it, eg: echo "|" =head1 HOME DIRECTORIES If a parameter starts with the character C<~> then the tilde may be expanded as a home directory path (either C<~> for the current user's home directory, or C<~user> for another user). Note that home directory expansion happens for users known I, not in the guest filesystem. To use a literal argument which begins with a tilde, you have to quote it, eg: echo "~" =head1 EXIT ON ERROR BEHAVIOUR By default, guestfish will ignore any errors when in interactive mode (ie. taking commands from a human over a tty), and will exit on the first error in non-interactive mode (scripts, commands given on the command line). If you prefix a command with a I<-> character, then that command will not cause guestfish to exit, even if that (one) command returns an error. =head1 REMOTE CONTROL GUESTFISH OVER A SOCKET Guestfish can be remote-controlled over a socket. This is useful particularly in shell scripts where you want to make several different changes to a filesystem, but you don't want the overhead of starting up a guestfish process each time. Start a guestfish server process using: eval `guestfish --listen` and then send it commands by doing: guestfish --remote cmd [...] To cause the server to exit, send it the exit command: guestfish --remote exit Note that the server will normally exit if there is an error in a command. You can change this in the usual way. See section I. =head2 CONTROLLING MULTIPLE GUESTFISH PROCESSES The C statement sets the environment variable C<$GUESTFISH_PID>, which is how the C<--remote> option knows where to send the commands. You can have several guestfish listener processes running using: eval `guestfish --listen` pid1=$GUESTFISH_PID eval `guestfish --listen` pid2=$GUESTFISH_PID ... guestfish --remote=$pid1 cmd guestfish --remote=$pid2 cmd =head2 STANDARD OUTPUT DURING REMOTE CONTROL Because of limitations in the C statement, stdout from the listener is currently redirected to C. Stderr is unchanged. =head2 REMOTE CONTROL DETAILS Remote control happens over a Unix domain socket called C, where C<$UID> is the effective user ID of the process, and C<$PID> is the process ID of the server. Guestfish client and server versions must match exactly. =head1 GUESTFISH COMMANDS The commands in this section are guestfish convenience commands, in other words, they are not part of the L API. =head2 alloc | allocate alloc filename size This creates an empty (zeroed) file of the given size, and then adds so it can be further examined. For more advanced image creation, see L utility. Size can be specified (where C means a number): =over 4 =item C or CK or CKB number of kilobytes, eg: C<1440> = standard 3.5in floppy =item CM or CMB number of megabytes =item CG or CGB number of gigabytes =item Csects number of 512 byte sectors =back =head2 echo echo [params ...] This echos the parameters to the terminal. =head2 edit | vi | emacs edit filename This is used to edit a file. It downloads the file, edits it locally using your editor, then uploads the result. The editor is C<$EDITOR>. However if you use the alternate commands C or C you will get those corresponding editors. NOTE: This will not work reliably for large files (> 2 MB) or binary files containing \0 bytes. =head2 glob glob command args... Expand wildcards in any paths in the args list, and run C repeatedly on each matching path. See section WILDCARDS AND GLOBBING. =head2 help help help cmd Without any parameter, this lists all commands. With a C parameter, this displays detailed help for a command. =head2 lcd lcd directory Change the local directory, ie. the current directory of guestfish itself. Note that C won't do what you might expect. =head2 more | less more filename less filename This is used to view a file. The default viewer is C<$PAGER>. However if you use the alternate command C you will get the C command specifically. NOTE: This will not work reliably for large files (> 2 MB) or binary files containing \0 bytes. =head2 quit | exit This exits guestfish. You can also use C<^D> key. =head2 reopen reopen Close and reopen the libguestfs handle. It is not necessary to use this normally, because the handle is closed properly when guestfish exits. However this is occasionally useful for testing. =head2 time time command args... Run the command as usual, but print the elapsed time afterwards. This can be useful for benchmarking operations. =head1 COMMANDS @ACTIONS@ =head1 ENVIRONMENT VARIABLES =over 4 =item EDITOR The C command uses C<$EDITOR> as the editor. If not set, it uses C. =item GUESTFISH_PID Used with the I<--remote> option to specify the remote guestfish process to control. See section I. =item HOME If compiled with GNU readline support, then the command history is saved in C<$HOME/.guestfish> =item LIBGUESTFS_APPEND Pass additional options to the guest kernel. =item LIBGUESTFS_DEBUG Set C to enable verbose messages. This has the same effect as using the B<-v> option. =item LIBGUESTFS_MEMSIZE Set the memory allocated to the qemu process, in megabytes. For example: LIBGUESTFS_MEMSIZE=700 =item LIBGUESTFS_PATH Set the path that guestfish uses to search for kernel and initrd.img. See the discussion of paths in L. =item LIBGUESTFS_QEMU Set the default qemu binary that libguestfs uses. If not set, then the qemu which was found at compile time by the configure script is used. =item PAGER The C command uses C<$PAGER> as the pager. If not set, it uses C. =item TMPDIR Location of temporary directory, defaults to C. If libguestfs was compiled to use the supermin appliance then each handle will require rather a large amount of space in this directory for short periods of time (~ 80 MB). You can use C<$TMPDIR> to configure another directory to use in case C is not large enough. =back =head1 EXIT CODE guestfish returns I<0> if the commands completed without error, or I<1> if there was an error. =head1 SEE ALSO L, L. =head1 AUTHORS Richard W.M. Jones (C) =head1 COPYRIGHT Copyright (C) 2009 Red Hat Inc. L 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 the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. 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.