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libguestfs/fish/guestfish.pod

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=encoding utf8
=head1 NAME
guestfish - the libguestfs Filesystem Interactive SHell
=head1 SYNOPSIS
guestfish [--options] [commands]
guestfish
guestfish -a disk.img
guestfish -a disk.img -m dev[:mountpoint]
guestfish -d libvirt-domain
guestfish -a disk.img -i
guestfish -d libvirt-domain -i
=head1 WARNING
Using guestfish in read/write mode on live virtual machines can be
dangerous, potentially causing disk corruption. Use the I<--ro>
(read-only) option to use guestfish safely if the disk image or
virtual machine might be live.
=head1 EXAMPLES
=head2 As an interactive shell
$ guestfish
Welcome to guestfish, the libguestfs filesystem interactive shell for
editing virtual machine filesystems.
Type: 'help' for a list of commands
'man' to read the manual
'quit' to quit the shell
><fs> man
=head2 From shell scripts
Create a new C</etc/motd> file in a guest:
guestfish <<_EOF_
add disk.img
run
mount /dev/vg_guest/lv_root /
write /etc/motd "Welcome, new users"
_EOF_
List the LVM logical volumes in a guest:
guestfish -a disk.img --ro <<_EOF_
run
lvs
_EOF_
=head2 On one command line
Update C</etc/resolv.conf> in a guest:
guestfish \
add disk.img : run : mount /dev/vg_guest/lv_root / : \
write /etc/resolv.conf "nameserver 1.2.3.4"
Edit C</boot/grub/grub.conf> interactively:
guestfish --add disk.img \
--mount /dev/vg_guest/lv_root \
--mount /dev/sda1:/boot \
edit /boot/grub/grub.conf
=head2 Mount disks automatically
Use the I<-i> option to automatically mount the
disks from a virtual machine:
guestfish --ro -a disk.img -i cat /etc/group
guestfish --ro -d libvirt-domain -i cat /etc/group
=head2 As a script interpreter
Create a 100MB disk containing an ext2-formatted partition:
#!/usr/bin/guestfish -f
sparse test1.img 100M
run
part-disk /dev/sda mbr
mkfs ext2 /dev/sda1
=head2 Start with a prepared disk
An alternate way to create a 100MB disk called C<test1.img> containing
a single ext2-formatted partition:
guestfish -N fs
To list what is available do:
guestfish -N help | less
=head2 Remote control
eval `guestfish --listen --ro`
guestfish --remote add disk.img
guestfish --remote run
guestfish --remote lvs
=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<guestfs(3)>.
Guestfish gives you structured access to the libguestfs API, from
shell scripts or the command line or interactively. If you want to
rescue a broken virtual machine image, you should look at the
L<virt-rescue(1)> command.
=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<cmd>.
=item B<-a image> | B<--add image>
Add a block device or virtual machine image to the shell.
=item B<-c URI> | B<--connect URI>
When used in conjunction with the I<-d> option, this specifies
the libvirt URI to use. The default is to use the default libvirt
connection.
=item B<-d libvirt-domain> | B<--domain libvirt-domain>
Add disks from the named libvirt domain. If the I<--ro> option is
also used, then any libvirt domain can be used. However in write
mode, only libvirt domains which are shut down can be named here.
=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<--echo-keys>
When prompting for keys and passphrases, guestfish normally turns
echoing off so you cannot see what you are typing. If you are not
worried about Tempest attacks and there is no one else in the room
you can specify this flag to see what you are typing.
=item B<-f file> | B<--file file>
Read commands from C<file>. To write pure guestfish
scripts, use:
#!/usr/bin/guestfish -f
=item B<-i> | B<--inspector>
Using L<virt-inspector(1)> code, inspect the disks looking for
an operating system and mount filesystems as they would be
mounted on the real virtual machine.
Typical usage is either:
guestfish -d myguest -i
(for an inactive libvirt domain called I<myguest>), or:
guestfish --ro -d myguest -i
(for active domains, readonly), or specify the block device directly:
guestfish -a /dev/Guests/MyGuest -i
Note that the command line syntax changed slightly over older
versions of guestfish. You can still use the old syntax:
guestfish [--ro] -i disk.img
guestfish [--ro] -i libvirt-domain
=item B<--keys-from-stdin>
Read key or passphrase parameters from stdin. The default is
to try to read passphrases from the user by opening C</dev/tty>.
=item B<--listen>
Fork into the background and listen for remote commands. See section
L</REMOTE CONTROL GUESTFISH OVER A SOCKET> 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 I<-m> or I<--mount> options are given, the guest is
automatically launched.
If you don't know what filesystems a disk image contains, you
can either run guestfish without this option, then list the partitions
and LVs available (see L</list-partitions> and L</lvs> commands),
or you can use the L<virt-list-filesystems(1)> program.
=item B<-n> | B<--no-sync>
Disable autosync. This is enabled by default. See the discussion
of autosync in the L<guestfs(3)> manpage.
=item B<-N type> | B<--new type> | B<-N help>
Prepare a fresh disk image formatted as "type". This is an
alternative to the I<-a> option: whereas I<-a> adds an existing disk,
I<-N> creates a preformatted disk with a filesystem and adds it.
See L</PREPARED DISK IMAGES> below.
=item B<--progress-bars>
Enable progress bars, even when guestfish is used non-interactively.
Progress bars are enabled by default when guestfish is used as an
interactive shell.
=item B<--no-progress-bars>
Disable progress bars.
=item B<--remote[=pid]>
Send remote commands to C<$GUESTFISH_PID> or C<pid>. See section
L</REMOTE CONTROL GUESTFISH OVER A SOCKET> below.
=item B<-r> | B<--ro>
This changes the I<-a> and I<-m> options so that disks are added and
mounts are done read-only (see L<guestfs(3)/guestfs_mount_ro>).
The option must always be used if the disk image or virtual machine
might be running, and is generally recommended in cases where you
don't need write access to the disk.
Note that prepared disk images created with I<-N> are not affected by
the I<--ro> option.
=item B<--selinux>
Enable SELinux support for the guest. See L<guestfs(3)/SELINUX>.
=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<guestfs(3)>, 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<run> is a synonym for C<launch>. You must C<launch> (or C<run>)
your guest before mounting or performing any other commands.
The only exception is that if the I<-m> or I<--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 whitespace-separated list, enclosed in quotes. Strings containing whitespace
to be passed through must be enclosed in single quotes. A literal single quote
must be escaped with a backslash.
vgcreate VG "/dev/sda1 /dev/sdb1"
command "/bin/echo 'foo bar'"
command "/bin/echo \'foo\'"
=head1 NUMBERS
This section applies to all commands which can take integers
as parameters.
=head2 SIZE SUFFIX
When the command takes a parameter measured in bytes, you can use one
of the following suffixes to specify kilobytes, megabytes and larger
sizes:
=over 4
=item B<k> or B<K> or B<KiB>
The size in kilobytes (multiplied by 1024).
=item B<KB>
The size in SI 1000 byte units.
=item B<M> or B<MiB>
The size in megabytes (multiplied by 1048576).
=item B<MB>
The size in SI 1000000 byte units.
=item B<G> or B<GiB>
The size in gigabytes (multiplied by 2**30).
=item B<GB>
The size in SI 10**9 byte units.
=item B<T> or B<TiB>
The size in terabytes (multiplied by 2**40).
=item B<TB>
The size in SI 10**12 byte units.
=item B<P> or B<PiB>
The size in petabytes (multiplied by 2**50).
=item B<PB>
The size in SI 10**15 byte units.
=item B<E> or B<EiB>
The size in exabytes (multiplied by 2**60).
=item B<EB>
The size in SI 10**18 byte units.
=item B<Z> or B<ZiB>
The size in zettabytes (multiplied by 2**70).
=item B<ZB>
The size in SI 10**21 byte units.
=item B<Y> or B<YiB>
The size in yottabytes (multiplied by 2**80).
=item B<YB>
The size in SI 10**24 byte units.
=back
For example:
truncate-size /file 1G
would truncate the file to 1 gigabyte.
Be careful because a few commands take sizes in kilobytes or megabytes
(eg. the parameter to L</memsize> is specified in megabytes already).
Adding a suffix will probably not do what you expect.
=head2 OCTAL AND HEXADECIMAL NUMBERS
For specifying the radix (base) use the C convention: C<0> to prefix
an octal number or C<0x> to prefix a hexadecimal number. For example:
1234 decimal number 1234
02322 octal number, equivalent to decimal 1234
0x4d2 hexadecimal number, equivalent to decimal 1234
When using the C<chmod> command, you almost always want to specify an
octal number for the mode, and you must prefix it with C<0> (unlike
the Unix L<chmod(1)> program):
chmod 0777 /public # OK
chmod 777 /public # WRONG! This is mode 777 decimal = 01411 octal.
Commands that return numbers usually print them in decimal, but
some commands print numbers in other radices (eg. C<umask> prints
the mode in octal, preceeded by C<0>).
=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</home/*>
then the above command will return an error.
To perform wildcard expansion, use the C<glob> command.
glob rm-rf /home/*
runs C<rm-rf> 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<glob> 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<not> 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</bin/sh> or whatever L<system(3)> uses).
For example:
!mkdir local
tgz-out /remote local/remote-data.tar.gz
will create a directory C<local> on the host, and then export
the contents of C</remote> on the mounted filesystem to
C<local/remote-data.tar.gz>. (See C<tgz-out>).
To change the local directory, use the C<lcd> command. C<!cd> will
have no effect, due to the way that subprocesses work in Unix.
=head1 PIPES
Use C<command E<lt>spaceE<gt> | 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<cat> is the guestfish cat command, but C<awk> 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
tgz-out / - | tar ztf -
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<on the
host>, not in the guest filesystem.
To use a literal argument which begins with a tilde, you have to quote
it, eg:
echo "~"
=head1 ENCRYPTED DISKS
Libguestfs has some support for Linux guests encrypted according to
the Linux Unified Key Setup (LUKS) standard, which includes nearly all
whole disk encryption systems used by modern Linux guests. Currently
only LVM-on-LUKS is supported.
Identify encrypted block devices and partitions using L</vfs-type>:
><fs> vfs-type /dev/sda2
crypto_LUKS
Then open those devices using L</luks-open>. This creates a
device-mapper device called C</dev/mapper/luksdev>.
><fs> luks-open /dev/sda2 luksdev
Enter key or passphrase ("key"): <enter the passphrase>
Finally you have to tell LVM to scan for volume groups on
the newly created mapper device:
><fs> vgscan
><fs> vg-activate-all true
The logical volume(s) can now be mounted in the usual way.
Before closing a LUKS device you must unmount any logical volumes on
it and deactivate the volume groups by calling C<vg-activate false VG>
on each one. Then you can close the mapper device:
><fs> vg-activate false /dev/VG
><fs> luks-close /dev/mapper/luksdev
=head1 WINDOWS PATHS
If a path is prefixed with C<win:> then you can use Windows-style
paths (with some limitations). The following commands are equivalent:
file /WINDOWS/system32/config/system.LOG
file win:/windows/system32/config/system.log
file win:\windows\system32\config\system.log
file WIN:C:\Windows\SYSTEM32\conFIG\SYSTEM.LOG
This syntax implicitly calls C<case-sensitive-path> (q.v.) so it also
handles case insensitivity like Windows would. This only works in
argument positions that expect a path.
=head1 UPLOADING AND DOWNLOADING FILES
For commands such as C<upload>, C<download>, C<tar-in>, C<tar-out> and
others which upload from or download to a local file, you can use the
special filename C<-> to mean "from stdin" or "to stdout". For example:
upload - /foo
reads stdin and creates from that a file C</foo> in the disk image,
and:
tar-out /etc - | tar tf -
writes the tarball to stdout and then pipes that into the external
"tar" command (see L</PIPES>).
When using C<-> to read from stdin, the input is read up to the end of
stdin. You can also use a special "heredoc"-like syntax to read up to
some arbitrary end marker:
upload -<<END /foo
input line 1
input line 2
input line 3
END
Any string of characters can be used instead of C<END>. The end
marker must appear on a line of its own, without any preceeding or
following characters (not even spaces).
Note that the C<-E<lt>E<lt>> syntax only applies to parameters used to
upload local files (so-called "FileIn" parameters in the generator).
=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
L</EXIT ON ERROR BEHAVIOUR>.
=head2 CONTROLLING MULTIPLE GUESTFISH PROCESSES
The C<eval> statement sets the environment variable C<$GUESTFISH_PID>,
which is how the I<--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 REMOTE CONTROL DETAILS
Remote control happens over a Unix domain socket called
C</tmp/.guestfish-$UID/socket-$PID>, 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 PREPARED DISK IMAGES
Use the I<-N type> or I<--new type> parameter to select one of a set
of preformatted disk images that guestfish can make for you to save
typing. This is particularly useful for testing purposes. This
option is used instead of the I<-a> option, and like I<-a> can appear
multiple times (and can be mixed with I<-a>).
The new disk is called C<test1.img> for the first I<-N>, C<test2.img>
for the second and so on. Existing files in the current directory are
I<overwritten>.
The type briefly describes how the disk should be sized, partitioned,
how filesystem(s) should be created, and how content should be added.
Optionally the type can be followed by extra parameters, separated by
C<:> (colon) characters. For example, I<-N fs> creates a default
100MB, sparsely-allocated disk, containing a single partition, with
the partition formatted as ext2. I<-N fs:ext4:1G> is the same, but
for an ext4 filesystem on a 1GB disk instead.
To list the available types and any extra parameters they take, run:
guestfish -N help | less
Note that the prepared filesystem is not mounted. You would usually
have to use the C<mount /dev/sda1 /> command or add the
I<-m /dev/sda1> option.
If any I<-N> or I<--new> options are given, the guest is automatically
launched.
=head2 EXAMPLES
Create a 100MB disk with an ext4-formatted partition:
guestfish -N fs:ext4
Create a 32MB disk with a VFAT-formatted partition, and mount it:
guestfish -N fs:vfat:32M -m /dev/sda1
Create a blank 200MB disk:
guestfish -N disk:200M
=head1 PROGRESS BARS
Some (not all) long-running commands send progress notification
messages as they are running. Guestfish turns these messages into
progress bars.
When a command that supports progress bars takes longer than two
seconds to run, and if progress bars are enabled, then you will see
one appearing below the command:
><fs> copy-size /large-file /another-file 2048M
/ 10% [#####-----------------------------------------] 00:30
The spinner on the left hand side moves round once for every progress
notification received from the backend. This is a (reasonably) golden
assurance that the command is "doing something" even if the progress
bar is not moving, because the command is able to send the progress
notifications. When the bar reaches 100% and the command finishes,
the spinner disappears.
Progress bars are enabled by default when guestfish is used
interactively. You can enable them even for non-interactive modes
using I<--progress-bars>, and you can disable them completely using
I<--no-progress-bars>.
=head1 GUESTFISH COMMANDS
The commands in this section are guestfish convenience commands, in
other words, they are not part of the L<guestfs(3)> API.
=head2 help
help
help cmd
Without any parameter, this lists all commands. With a C<cmd>
parameter, this displays detailed help for a command.
=head2 quit | exit
This exits guestfish. You can also use C<^D> key.
@FISH_COMMANDS@
=head1 COMMANDS
@ACTIONS@
=head1 EXIT CODE
guestfish returns 0 if the commands completed without error, or
1 if there was an error.
=head1 ENVIRONMENT VARIABLES
=over 4
=item EDITOR
The C<edit> command uses C<$EDITOR> as the editor. If not
set, it uses C<vi>.
=item GUESTFISH_PID
Used with the I<--remote> option to specify the remote guestfish
process to control. See section
L</REMOTE CONTROL GUESTFISH OVER A SOCKET>.
=item HOME
If compiled with GNU readline support, various files in the
home directory can be used. See L</FILES>.
=item LIBGUESTFS_APPEND
Pass additional options to the guest kernel.
=item LIBGUESTFS_DEBUG
Set C<LIBGUESTFS_DEBUG=1> to enable verbose messages. This has the
same effect as using the B<-v> option.
=item LIBGUESTFS_MEMSIZE
Set the memory allocated to the qemu process, in megabytes. For
example:
LIBGUESTFS_MEMSIZE=700
=item LIBGUESTFS_PATH
Set the path that guestfish uses to search for kernel and initrd.img.
See the discussion of paths in L<guestfs(3)>.
=item LIBGUESTFS_QEMU
Set the default qemu binary that libguestfs uses. If not set, then
the qemu which was found at compile time by the configure script is
used.
=item LIBGUESTFS_TRACE
Set C<LIBGUESTFS_TRACE=1> to enable command traces.
=item PAGER
The C<more> command uses C<$PAGER> as the pager. If not
set, it uses C<more>.
=item TMPDIR
Location of temporary directory, defaults to C</tmp>.
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</tmp> is not large
enough.
=back
=head1 FILES
=over 4
=item $HOME/.guestfish
If compiled with GNU readline support, then the command history
is saved in this file.
=item $HOME/.inputrc
=item /etc/inputrc
If compiled with GNU readline support, then these files can be used to
configure readline. For further information, please see
L<readline(3)/INITIALIZATION FILE>.
To write rules which only apply to guestfish, use:
$if guestfish
...
$endif
Variables that you can set in inputrc that change the behaviour
of guestfish in useful ways include:
=over 4
=item completion-ignore-case (default: on)
By default, guestfish will ignore case when tab-completing
paths on the disk. Use:
set completion-ignore-case off
to make guestfish case sensitive.
=back
=item test1.img
=item test2.img (etc)
When using the C<-N> or C<--new> option, the prepared disk or
filesystem will be created in the file C<test1.img> in the current
directory. The second use of C<-N> will use C<test2.img> and so on.
Any existing file with the same name will be overwritten.
=back
=head1 SEE ALSO
L<guestfs(3)>,
L<http://libguestfs.org/>,
L<virt-cat(1)>,
L<virt-df(1)>,
L<virt-edit(1)>,
L<virt-list-filesystems(1)>,
L<virt-list-partitions(1)>,
L<virt-ls(1)>,
L<virt-make-fs(1)>,
L<virt-rescue(1)>,
L<virt-resize(1)>,
L<virt-tar(1)>,
L<virt-win-reg(1)>.
=head1 AUTHORS
Richard W.M. Jones (C<rjones at redhat dot com>)
=head1 COPYRIGHT
Copyright (C) 2009-2010 Red Hat Inc.
L<http://libguestfs.org/>
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.