VIRSH(1) Virtualization Support VIRSH(1)NAMEvirsh - management user interface
SYNOPSISvirsh [OPTION]... [COMMAND_STRING]
virsh [OPTION]... COMMAND [ARG]...
DESCRIPTION
The virsh program is the main interface for managing virsh guest
domains. The program can be used to create, pause, and shutdown
domains. It can also be used to list current domains. Libvirt is a C
toolkit to interact with the virtualization capabilities of recent
versions of Linux (and other OSes). It is free software available under
the GNU Lesser General Public License. Virtualization of the Linux
Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the
basic resources are driven by a Linux instance. The library aims at
providing a long term stable C API. It currently supports Xen, QEmu,
KVM, LXC, OpenVZ, VirtualBox and VMware ESX.
The basic structure of most virsh usage is:
virsh [OPTION]... <command> <domain-id> [ARG]...
Where command is one of the commands listed below, domain-id is the
numeric domain id, or the domain name (which will be internally
translated to domain id), and ARGS are command specific options. There
are a few exceptions to this rule in the cases where the command in
question acts on all domains, the entire machine, or directly on the
xen hypervisor. Those exceptions will be clear for each of those
commands.
The virsh program can be used either to run one COMMAND by giving the
command and its arguments on the shell command line, or a
COMMAND_STRING which is a single shell argument consisting of multiple
COMMAND actions and their arguments joined with whitespace, and
separated by semicolons between commands. Within COMMAND_STRING, virsh
understands the same single, double, and backslash escapes as the
shell, although you must add another layer of shell escaping in
creating the single shell argument. If no command is given in the
command line, virsh will then start a minimal interpreter waiting for
your commands, and the quit command will then exit the program.
The virsh program understands the following OPTIONS.
-h, --help
Ignore all other arguments, and behave as if the help command were
given instead.
-v, --version[=short]
Ignore all other arguments, and prints the version of the libvirt
library virsh is coming from
-V, --version=long
Ignore all other arguments, and prints the version of the libvirt
library virsh is coming from and which options and driver are
compiled in.
-c, --connect URI
Connect to the specified URI, as if by the connect command, instead
of the default connection.
-d, --debug LEVEL
Enable debug messages at integer LEVEL and above. LEVEL can range
from 0 to 4 (default). See the documentation of VIRSH_DEBUG
environment variable for the description of each LEVEL.
-l, --log FILE
Output logging details to FILE.
-q, --quiet
Avoid extra informational messages.
-r, --readonly
Make the initial connection read-only, as if by the --readonly
option of the connect command.
-t, --timing
Output elapsed time information for each command.
NOTES
Most virsh operations rely upon the libvirt library being able to
connect to an already running libvirtd service. This can usually be
done using the command service libvirtd start.
Most virsh commands require root privileges to run due to the
communications channels used to talk to the hypervisor. Running as non
root will return an error.
Most virsh commands act synchronously, except maybe shutdown, setvcpus
and setmem. In those cases the fact that the virsh program returned,
may not mean the action is complete and you must poll periodically to
detect that the guest completed the operation.
GENERIC COMMANDS
The following commands are generic i.e. not specific to a domain.
help [command-or-group]
This lists each of the virsh commands. When used without options,
all commands are listed, one per line, grouped into related
categories, displaying the keyword for each group.
To display only commands for a specific group, give the keyword for
that group as an option. For example:
virsh # help host
Host and Hypervisor (help keyword 'host'):
capabilities capabilities
connect (re)connect to hypervisor
freecell NUMA free memory
hostname print the hypervisor hostname
qemu-attach Attach to existing QEMU process
qemu-monitor-command QEMU Monitor Command
sysinfo print the hypervisor sysinfo
uri print the hypervisor canonical URI
To display detailed information for a specific command, give its
name as the option instead. For example:
virsh # help list
NAME
list - list domains
SYNOPSIS
list [--inactive] [--all]
DESCRIPTION
Returns list of domains.
OPTIONS
--inactive list inactive domains
--all list inactive & active domains
quit, exit
quit this interactive terminal
version
Will print out the major version info about what this built from.
Example
virsh version
Compiled against library: libvir 0.0.6
Using library: libvir 0.0.6
Using API: Xen 3.0.0
Running hypervisor: Xen 3.0.0
cd [directory]
Will change current directory to directory. The default directory
for the cd command is the home directory or, if there is no HOME
variable in the environment, the root directory.
This command is only available in interactive mode.
pwd Will print the current directory.
connect URI [--readonly]
(Re)-Connect to the hypervisor. When the shell is first started,
this is automatically run with the URI parameter requested by the
"-c" option on the command line. The URI parameter specifies how to
connect to the hypervisor. The documentation page at
<http://libvirt.org/uri.html> list the values supported, but the
most common are:
xen:///
this is used to connect to the local Xen hypervisor, this is
the default
qemu:///system
connect locally as root to the daemon supervising QEmu and KVM
domains
qemu:///session
connect locally as a normal user to his own set of QEmu and KVM
domains
lxc:///
connect to a local linux container
For remote access see the documentation page on how to make URIs.
The --readonly option allows for read-only connection
uri Prints the hypervisor canonical URI, can be useful in shell mode.
hostname
Print the hypervisor hostname.
sysinfo
Print the XML representation of the hypervisor sysinfo, if
available.
nodeinfo
Returns basic information about the node, like number and type of
CPU, and size of the physical memory. The output corresponds to
virNodeInfo structure. Specifically, the "CPU socket(s)" field
means number of CPU sockets per NUMA cell.
nodecpustats [cpu] [--percent]
Returns cpu stats of the node. If cpu is specified, this will
prints specified cpu statistics only. If --percent is specified,
this will prints percentage of each kind of cpu statistics during 1
second.
nodememstats [cell]
Returns memory stats of the node. If cell is specified, this will
prints specified cell statistics only.
capabilities
Print an XML document describing the capabilities of the hypervisor
we are currently connected to. This includes a section on the host
capabilities in terms of CPU and features, and a set of description
for each kind of guest which can be virtualized. For a more
complete description see:
<http://libvirt.org/formatcaps.html> The XML also show the NUMA
topology information if available.
inject-nmi domain-id
Inject NMI to the guest.
list [--inactive | --all] [--managed-save]
Prints information about existing domains. If no options are
specified it prints out information about running domains.
An example format for the list is as follows:
virsh list
Id Name State
----------------------------------
0 Domain-0 running
2 fedora paused
Name is the name of the domain. ID the domain numeric id. State
is the run state (see below).
STATES
The State field lists 7 states for a domain, and which ones the
current domain is in.
running
The domain is currently running on a CPU
idle
The domain is idle, and not running or runnable. This can be
caused because the domain is waiting on IO (a traditional wait
state) or has gone to sleep because there was nothing else for
it to do.
paused
The domain has been paused, usually occurring through the
administrator running virsh suspend. When in a paused state
the domain will still consume allocated resources like memory,
but will not be eligible for scheduling by the hypervisor.
send-key domain-id [--codeset codeset] [--holdtime holdtime]
keycode...
Parse the keycode sequence as keystrokes to send to domain-id.
Each keycode can either be a numeric value or a symbolic name
from the corresponding codeset. If --holdtime is given, each
keystroke will be held for that many milliseconds. The default
codeset is linux, but use of the --codeset option allows other
codesets to be chosen.
linux
The numeric values are those defined by the Linux generic
input event subsystem. The symbolic names match the
corresponding Linux key constant macro names.
xt The numeric values are those defined by the original XT
keyboard controller. No symbolic names are provided
atset1
The numeric values are those defined by the AT keyboard
controller, set 1 (aka XT compatible set). Extended keycoes
from atset1 may differ from extended keycodes in the xt
codeset. No symbolic names are provided
atset2
The numeric values are those defined by the AT keyboard
controller, set 2. No symbolic names are provided
atset3
The numeric values are those defined by the AT keyboard
controller, set 3 (aka PS/2 compatible set). No symbolic
names are provided
os_x
The numeric values are those defined by the OS-X keyboard
input subsystem. The symbolic names match the corresponding
OS-X key constant macro names
xt_kbd
The numeric values are those defined by the Linux KBD
device. These are a variant on the original XT codeset,
but often with different encoding for extended keycodes. No
symbolic names are provided.
win32
The numeric values are those defined by the Win32 keyboard
input subsystem. The symbolic names match the corresponding
Win32 key constant macro names
usb The numeric values are those defined by the USB HID
specification for keyboard input. No symbolic names are
provided
rfb The numeric values are those defined by the RFB extension
for sending raw keycodes. These are a variant on the XT
codeset, but extended keycodes have the low bit of the
second byte set, instead of the high bit of the first byte.
No symbolic names are provided.
Examples
# send three strokes 'k', 'e', 'y', using xt codeset
virsh send-key dom --codeset xt 37 18 21
# send one stroke 'right-ctrl+C'
virsh send-key dom KEY_RIGHTCTRL KEY_C
# send a tab, held for 1 second
virsh send-key --holdtime 1000 0xf
shutdown
The domain is in the process of shutting down, i.e. the guest
operating system has been notified and should be in the process
of stopping its operations gracefully.
shut off
The domain is not running. Usually this indicates the domain
has been shut down completely, or has not been started.
crashed
The domain has crashed, which is always a violent ending.
Usually this state can only occur if the domain has been
configured not to restart on crash.
dying
The domain is in process of dying, but hasn't completely
shutdown or crashed.
If --managed-save is specified, then domains that have managed save
state (only possible if they are in the shut off state) will
instead show as saved in the listing.
freecell [cellno | --all]
Prints the available amount of memory on the machine or within a
NUMA cell if cellno is provided. If --all is provided instead of
--cellno, then show the information on all NUMA cells.
cpu-baseline FILE
Compute baseline CPU which will be supported by all host CPUs given
in <file>. The list of host CPUs is built by extracting all <cpu>
elements from the <file>. Thus, the <file> can contain either a set
of <cpu> elements separated by new lines or even a set of complete
<capabilities> elements printed by capabilities command.
cpu-compare FILE
Compare CPU definition from XML <file> with host CPU. The XML
<file> may contain either host or guest CPU definition. The host
CPU definition is the <cpu> element and its contents as printed by
capabilities command. The guest CPU definition is the <cpu> element
and its contents from domain XML definition. For more information
on guest CPU definition see:
<http://libvirt.org/formatdomain.html#elementsCPU>
DOMAIN COMMANDS
The following commands manipulate domains directly, as stated
previously most commands take domain-id as the first parameter. The
domain-id can be specified as a short integer, a name or a full UUID.
autostart [--disable] domain-id
Configure a domain to be automatically started at boot.
The option --disable disables autostarting.
console domain-id [devname]
Connect the virtual serial console for the guest. The optional
devname parameter refers to the device alias of an alternate
console, serial or parallel device configured for the guest. If
omitted, the primary console will be opened.
create FILE [--console] [--paused] [--autodestroy]
Create a domain from an XML <file>. An easy way to create the XML
<file> is to use the dumpxml command to obtain the definition of a
pre-existing guest. The domain will be paused if the --paused
option is used and supported by the driver; otherwise it will be
running. If --console is requested, attach to the console after
creation. If --autodestroy is requested, then the guest will be
automatically destroyed when virsh closes its connection to
libvirt, or otherwise exits.
Example
virsh dumpxml <domain-id> > domain.xml
vi domain.xml (or make changes with your other text editor)
virsh create < domain.xml
define FILE
Define a domain from an XML <file>. The domain definition is
registered but not started.
destroy domain-id
Immediately terminate the domain domain-id. This doesn't give the
domain OS any chance to react, and it's the equivalent of ripping
the power cord out on a physical machine. In most cases you will
want to use the shutdown command instead. However, this does not
delete any storage volumes used by the guest, and if the domain is
persistent, it can be restarted later.
If domain-id is transient, then the metadata of any snapshots will
be lost once the guest stops running, but the snapshot contents
still exist, and a new domain with the same name and UUID can
restore the snapshot metadata with snapshot-create.
domblkstat domain block-device [--human]
Get device block stats for a running domain. A block-device
corresponds to a unique target name (<target dev='name'/>) or
source file (<source file='name'/>) for one of the disk devices
attached to domain (see also domblklist for listing these names).
Use --human for a more human readable output.
Availability of these fields depends on hypervisor. Unsupported
fields are missing from the output. Other fields may appear if
communicating with a newer version of libvirtd.
Explanation of fields (fields appear in the folowing order):
rd_req - count of read operations
rd_bytes - count of read bytes
wr_req - count of write operations
wr_bytes - count of written bytes
errs - error count
flush_operations - count of flush operations
rd_total_times - total time read operations took (ns)
wr_total_times - total time write operations took (ns)
flush_total_times - total time flush operations took (ns)
<-- other fields provided by hypervisor -->
domifstat domain interface-device
Get network interface stats for a running domain.
domif-setlink domain interface-MAC state --persistent
Modify link state of the domain's virtual interface. Possible
values for state are "up" and "down. If --persistent is specified,
only the persistent configuration of the domain is modified.
domif-getlink domain interface-MAC --persistent
Query link state of the domain's virtual interface. If --persistent
is specified, query the persistent configuration.
dommemstat domain
Get memory stats for a running domain.
domblkinfo domain block-device
Get block device size info for a domain. A block-device
corresponds to a unique target name (<target dev='name'/>) or
source file (<source file='name'/>) for one of the disk devices
attached to domain (see also domblklist for listing these names).
domblklist domain [--inactive]
Print a table showing the names of all block devices associated
with domain, as well as the path to the source of each device. If
--inactive is specified, query the block devices that will be used
on the next boot, rather than those currently in use by a running
domain. Other contexts that require a block device name (such as
domblkinfo or snapshot-create for disk snapshots) will accept
either target or unique source names printed by this command.
blockpull domain path [bandwidth]
Populate a disk from its backing image. Once all data from its
backing image has been pulled, the disk no longer depends on the
backing image. It pulls data for the entire disk in the
background, the process of the operation can be checked with
blockjob.
path specifies fully-qualified path of the disk. bandwidth
specifies copying bandwidth limit in Mbps.
blockjob domain path [--abort] [--info] [bandwidth]
Manage active block operations.
path specifies fully-qualified path of the disk. If --abort is
specified, the active job on the specified disk will be aborted.
If --info is specified, the active job information on the specified
disk will be printed. bandwidth can be used to set bandwidth limit
for the active job.
dominfo domain-id
Returns basic information about the domain.
domuuid domain-name-or-id
Convert a domain name or id to domain UUID
domid domain-name-or-uuid
Convert a domain name (or UUID) to a domain id
domjobabort domain-id-or-uuid
Abort the currently running domain job.
domjobinfo domain-id-or-uuid
Returns information about jobs running on a domain.
domname domain-id-or-uuid
Convert a domain Id (or UUID) to domain name
domstate domain-id [--reason]
Returns state about a domain. --reason tells virsh to also print
reason for the state.
domcontrol domain-id
Returns state of an interface to VMM used to control a domain. For
states other than "ok" or "error" the command also prints number of
seconds elapsed since the control interface entered its current
state.
domxml-from-native format config
Convert the file config in the native guest configuration format
named by format to a domain XML format.
domxml-to-native format xml
Convert the file xml in domain XML format to the native guest
configuration format named by format.
dump domain-id corefilepath [--live] [--crash] [--bypass-cache]
Dumps the core of a domain to a file for analysis. If --live is
specified, the domain continues to run until the core dump is
complete, rather than pausing up front. If --crash is specified,
the domain is halted with a crashed status, rather than merely left
in a paused state. If --bypass-cache is specified, the save will
avoid the file system cache, although this may slow down the
operation.
NOTE: Some hypervisors may require the user to manually ensure
proper permissions on file and path specified by argument
corefilepath.
dumpxml domain-id [--inactive] [--security-info] [--update-cpu]
Output the domain information as an XML dump to stdout, this format
can be used by the create command. Additional options affecting the
XML dump may be used. --inactive tells virsh to dump domain
configuration that will be used on next start of the domain as
opposed to the current domain configuration. Using --security-info
will also include security sensitive information in the XML dump.
--update-cpu updates domain CPU requirements according to host CPU.
echo [--shell] [--xml] [arg...]
Echo back each arg, separated by space. If --shell is specified,
then the output will be single-quoted where needed, so that it is
suitable for reuse in a shell context. If --xml is specified, then
the output will be escaped for use in XML.
edit domain-id
Edit the XML configuration file for a domain.
This is equivalent to:
virsh dumpxml domain > domain.xml
vi domain.xml (or make changes with your other text editor)
virsh define domain.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
managedsave domain-id [--bypass-cache] [{--running | --paused}]
Save and destroy (stop) a running domain, so it can be restarted
from the same state at a later time. When the virsh start command
is next run for the domain, it will automatically be started from
this saved state. If --bypass-cache is specified, the save will
avoid the file system cache, although this may slow down the
operation.
Normally, starting a managed save will decide between running or
paused based on the state the domain was in when the save was done;
passing either the --running or --paused flag will allow overriding
which state the start should use.
The dominfo command can be used to query whether a domain currently
has any managed save image.
managedsave-remove domain-id
Remove the managedsave state file for a domain, if it exists. This
ensures the domain will do a full boot the next time it is started.
maxvcpus [type]
Provide the maximum number of virtual CPUs supported for a guest VM
on this connection. If provided, the type parameter must be a
valid type attribute for the <domain> element of XML.
migrate [--live] [--direct] [--p2p [--tunnelled]] [--persistent]
[--undefinesource] [--suspend] [--copy-storage-all]
[--copy-storage-inc] [--change-protection] [--verbose] domain-id
desturi [migrateuri] [dname] [--timeout seconds] [--xml file]
Migrate domain to another host. Add --live for live migration;
--p2p for peer-2-peer migration; --direct for direct migration; or
--tunnelled for tunnelled migration. --persistent leaves the
domain persistent on destination host, --undefinesource undefines
the domain on the source host, and --suspend leaves the domain
paused on the destination host. --copy-storage-all indicates
migration with non-shared storage with full disk copy,
--copy-storage-inc indicates migration with non-shared storage with
incremental copy (same base image shared between source and
destination). --change-protection enforces that no incompatible
configuration changes will be made to the domain while the
migration is underway; this flag is implicitly enabled when
supported by the hypervisor, but can be explicitly used to reject
the migration if the hypervisor lacks change protection support.
--verbose displays the progress of migration.
The desturi is the connection URI of the destination host, and
migrateuri is the migration URI, which usually can be omitted.
dname is used for renaming the domain to new name during migration,
which also usually can be omitted. Likewise, --xml file is usually
omitted, but can be used to supply an alternative XML file for use
on the destination to supply a larger set of changes to any host-
specific portions of the domain XML, such as accounting for naming
differences between source and destination in accessing underlying
storage.
--timeout seconds forces guest to suspend when live migration
exceeds that many seconds, and then the migration will complete
offline. It can only be used with --live.
Note: The desturi parameter for normal migration and peer2peer
migration has different semantics:
· normal migration: the desturi is an address of the target host
as seen from the client machine.
· peer2peer migration: the desturi is an address of the target
host as seen from the source machine.
migrate-setmaxdowntime domain-id downtime
Set maximum tolerable downtime for a domain which is being live-
migrated to another host. The downtime is a number of milliseconds
the guest is allowed to be down at the end of live migration.
migrate-setspeed domain-id bandwidth
Set the maximum migration bandwidth (in Mbps) for a domain which is
being migrated to another host.
migrate-getspeed domain-id
Get the maximum migration bandwidth (in Mbps) for a domain.
reboot domain-id
Reboot a domain. This acts just as if the domain had the reboot
command run from the console. The command returns as soon as it
has executed the reboot action, which may be significantly before
the domain actually reboots.
The exact behavior of a domain when it reboots is set by the
on_reboot parameter in the domain's XML definition.
restore state-file [--bypass-cache] [--xml file] [{--running |
--paused}]
Restores a domain from a virsh save state file. See save for more
info.
If --bypass-cache is specified, the restore will avoid the file
system cache, although this may slow down the operation.
--xml file is usually omitted, but can be used to supply an
alternative XML file for use on the restored guest with changes
only in the host-specific portions of the domain XML. For example,
it can be used to account for file naming differences in underlying
storage due to disk snapshots taken after the guest was saved.
Normally, restoring a saved image will use the state recorded in
the save image to decide between running or paused; passing either
the --running or --paused flag will allow overriding which state
the domain should be started in.
Note: To avoid corrupting file system contents within the domain,
you should not reuse the saved state file for a second restore
unless you have also reverted all storage volumes back to the same
contents as when the state file was created.
save domain-id state-file [--bypass-cache] [--xml file] [{--running |
--paused}]
Saves a running domain (RAM, but not disk state) to a state file so
that it can be restored later. Once saved, the domain will no
longer be running on the system, thus the memory allocated for the
domain will be free for other domains to use. virsh restore
restores from this state file. If --bypass-cache is specified, the
save will avoid the file system cache, although this may slow down
the operation.
This is roughly equivalent to doing a hibernate on a running
computer, with all the same limitations. Open network connections
may be severed upon restore, as TCP timeouts may have expired.
--xml file is usually omitted, but can be used to supply an
alternative XML file for use on the restored guest with changes
only in the host-specific portions of the domain XML. For example,
it can be used to account for file naming differences that are
planned to be made via disk snapshots of underlying storage after
the guest is saved.
Normally, restoring a saved image will decide between running or
paused based on the state the domain was in when the save was done;
passing either the --running or --paused flag will allow overriding
which state the restore should use.
Domain saved state files assume that disk images will be unchanged
between the creation and restore point. For a more complete system
restore point, where the disk state is saved alongside the memory
state, see the snapshot family of commands.
save-image-define file xml [{--running | --paused}]
Update the domain XML that will be used when file is later used in
the restore command. The xml argument must be a file name
containing the alternative XML, with changes only in the host-
specific portions of the domain XML. For example, it can be used
to account for file naming differences resulting from creating disk
snapshots of underlying storage after the guest was saved.
The save image records whether the domain should be restored to a
running or paused state. Normally, this command does not alter the
recorded state; passing either the --running or --paused flag will
allow overriding which state the restore should use.
save-image-dumpxml file [--security-info]
Extract the domain XML that was in effect at the time the saved
state file file was created with the save command. Using
--security-info will also include security sensitive information.
save-image-edit file [{--running | --paused}]
Edit the XML configuration associated with a saved state file file
created by the save command.
The save image records whether the domain should be restored to a
running or paused state. Normally, this command does not alter the
recorded state; passing either the --running or --paused flag will
allow overriding which state the restore should use.
This is equivalent to:
virsh save-image-dumpxml state-file > state-file.xml
vi state-file.xml (or make changes with your other text editor)
virsh save-image-define state-file state-file-xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
schedinfo [--set parameter=value] domain-id [[--config] [--live] |
[--current]]
schedinfo [--weight number] [--cap number] domain-id
Allows you to show (and set) the domain scheduler parameters. The
parameters available for each hypervisor are:
LXC (posix scheduler) : cpu_shares
QEMU/KVM (posix scheduler): cpu_shares, vcpu_period, vcpu_quota
Xen (credit scheduler): weight, cap
ESX (allocation scheduler): reservation, limit, shares
If --live is specified, set scheduler information of a running
guest. If --config is specified, affect the next boot of a
persistent guest. If --current is specified, affect the current
guest state.
Note: The cpu_shares parameter has a valid value range of 0-262144;
Negative values are wrapped to positive, and larger values are
capped at the maximum. Therefore, -1 is a useful shorthand for
262144.
Note: The weight and cap parameters are defined only for the
XEN_CREDIT scheduler and are now DEPRECATED.
Note: The vcpu_period parameter has a valid value range of
1000-1000000 or 0, and the vcpu_quota parameter has a valid value
range of 1000-18446744073709551 or less than 0. The value 0 for
either parameter is the same as not specifying that parameter.
screenshot domain-id [imagefilepath] [--screen screenID]
Takes a screenshot of a current domain console and stores it into a
file. Optionally, if hypervisor supports more displays for a
domain, screenID allows to specify which screen will be captured.
It is the sequential number of screen. In case of multiple graphics
cards, heads are enumerated before devices, e.g. having two
graphics cards, both with four heads, screen ID 5 addresses the
second head on the second card.
setmem domain-id kilobytes [[--config] [--live] | [--current]]
Change the memory allocation for a guest domain. If --live is
specified, perform a memory balloon of a running guest. If
--config is specified, affect the next boot of a persistent guest.
If --current is specified, affect the current guest state. Both
--live and --config flags may be given, but --current is exclusive.
If no flag is specified, behavior is different depending on
hypervisor.
Some hypervisors require a larger granularity than kilobytes, and
requests that are not an even multiple will be rounded up. For
example, vSphere/ESX rounds the parameter up unless the kB argument
is evenly divisible by 1024 (that is, the kB argument happens to
represent megabytes).
For Xen, you can only adjust the memory of a running domain if the
domain is paravirtualized or running the PV balloon driver.
setmaxmem domain-id kilobytes [[--config] [--live] | [--current]]
Change the maximum memory allocation limit for a guest domain. If
--live is specified, affect a running guest. If --config is
specified, affect the next boot of a persistent guest. If
--current is specified, affect the current guest state. Both
--live and --current flags may be given, but --current is
exclusive. If no flag is specified, behavior is different depending
on hypervisor.
This command works for at least the Xen, QEMU/KVM and vSphere/ESX
hypervisors.
Some hypervisors require a larger granularity than kilobytes,
rounding up requests that are not an even multiple of the desired
amount. vSphere/ESX is one of these, requiring the parameter to be
evenly divisible by 4MB. For vSphere/ESX, 263168 (257MB) would be
rounded up because it's not a multiple of 4MB, while 266240 (260MB)
is valid without rounding.
memtune domain-id [--hard-limit kilobytes] [--soft-limit kilobytes]
[--swap-hard-limit kilobytes] [--min-guarantee kilobytes] [[--config]
[--live] | [--current]]
Allows you to display or set the domain memory parameters. Without
flags, the current settings are displayed; with a flag, the
appropriate limit is adjusted if supported by the hypervisor. LXC
and QEMU/KVM support --hard-limit, --soft-limit, and
--swap-hard-limit.
If --live is specified, affect a running guest. If --config is
specified, affect the next boot of a persistent guest. If
--current is specified, affect the current guest state. Both
--live and --current flags may be given, but --current is
exclusive. If no flag is specified, behavior is different depending
on hypervisor.
For QEMU/KVM, the parameters are applied to the QEMU process as a
whole. Thus, when counting them, one needs to add up guest RAM,
guest video RAM, and some memory overhead of QEMU itself. The last
piece is hard to determine so one needs guess and try.
--hard-limit
The maximum memory the guest can use. The units for this value
are kilobytes (i.e. blocks of 1024 bytes).
--soft-limit
The memory limit to enforce during memory contention. The
units for this value are kilobytes (i.e. blocks of 1024 bytes).
--swap-hard-limit
The maximum memory plus swap the guest can use. The units for
this value are kilobytes (i.e. blocks of 1024 bytes). This has
to be more than hard-limit value provided.
--min-guarantee
The guaranteed minimum memory allocation for the guest. The
units for this value are kilobytes (i.e. blocks of 1024 bytes).
blkiotune domain-id [--weight weight] [[--config] [--live] |
[--current]]
Display or set the blkio parameters. QEMU/KVM supports --weight.
--weight is in range [100, 1000].
If --live is specified, affect a running guest. If --config is
specified, affect the next boot of a persistent guest. If
--current is specified, affect the current guest state. Both
--live and --current flags may be given, but --current is
exclusive. If no flag is specified, behavior is different depending
on hypervisor.
setvcpus domain-id count [--maximum] [[--config] [--live] |
[--current]]
Change the number of virtual CPUs active in a guest domain. By
default, this command works on active guest domains. To change the
settings for an inactive guest domain, use the --config flag.
The count value may be limited by host, hypervisor, or a limit
coming from the original description of the guest domain. For Xen,
you can only adjust the virtual CPUs of a running domain if the
domain is paravirtualized.
If the --config flag is specified, the change is made to the stored
XML configuration for the guest domain, and will only take effect
when the guest domain is next started.
If --live is specified, the guest domain must be active, and the
change takes place immediately. Both the --config and --live flags
may be specified together if supported by the hypervisor.
If --current is specified, affect the current guest state.
When no flags are given, the --live flag is assumed and the guest
domain must be active. In this situation it is up to the
hypervisor whether the --config flag is also assumed, and therefore
whether the XML configuration is adjusted to make the change
persistent.
The --maximum flag controls the maximum number of virtual cpus that
can be hot-plugged the next time the domain is booted. As such, it
must only be used with the --config flag, and not with the --live
flag.
shutdown domain-id
Gracefully shuts down a domain. This coordinates with the domain
OS to perform graceful shutdown, so there is no guarantee that it
will succeed, and may take a variable length of time depending on
what services must be shutdown in the domain.
The exact behavior of a domain when it shuts down is set by the
on_shutdown parameter in the domain's XML definition.
If domain-id is transient, then the metadata of any snapshots will
be lost once the guest stops running, but the snapshot contents
still exist, and a new domain with the same name and UUID can
restore the snapshot metadata with snapshot-create.
start domain-name [--console] [--paused] [--autodestroy]
[--bypass-cache] [--force-boot]
Start a (previously defined) inactive domain, either from the last
managedsave state, or via a fresh boot if no managedsave state is
present. The domain will be paused if the --paused option is used
and supported by the driver; otherwise it will be running. If
--console is requested, attach to the console after creation. If
--autodestroy is requested, then the guest will be automatically
destroyed when virsh closes its connection to libvirt, or otherwise
exits. If --bypass-cache is specified, and managedsave state
exists, the restore will avoid the file system cache, although this
may slow down the operation. If --force-boot is specified, then
any managedsave state is discarded and a fresh boot occurs.
suspend domain-id
Suspend a running domain. It is kept in memory but won't be
scheduled anymore.
resume domain-id
Moves a domain out of the suspended state. This will allow a
previously suspended domain to now be eligible for scheduling by
the underlying hypervisor.
ttyconsole domain-id
Output the device used for the TTY console of the domain. If the
information is not available the processes will provide an exit
code of 1.
undefine domain-id [--managed-save] [--snapshots-metadata]
Undefine a domain. If the domain is running, this converts it to a
transient domain, without stopping it. If the domain is inactive,
the domain configuration is removed.
The --managed-save flag guarantees that any managed save image (see
the managedsave command) is also cleaned up. Without the flag,
attempts to undefine a domain with a managed save image will fail.
The --snapshots-metadata flag guarantees that any snapshots (see
the snapshot-list command) are also cleaned up when undefining an
inactive domain. Without the flag, attempts to undefine an
inactive domain with snapshot metadata will fail. If the domain is
active, this flag is ignored.
NOTE: For an inactive domain, the domain name or UUID must be used
as the domain-id.
vcpucount domain-id [{--maximum | --active} {--config | --live |
--current}]
Print information about the virtual cpu counts of the given domain-
id. If no flags are specified, all possible counts are listed in a
table; otherwise, the output is limited to just the numeric value
requested. For historical reasons, the table lists the label
"current" on the rows that can be queried in isolation via the
--active flag, rather than relating to the --current flag.
--maximum requests information on the maximum cap of vcpus that a
domain can add via setvcpus, while --active shows the current
usage; these two flags cannot both be specified. --config requires
a persistent domain and requests information regarding the next
time the domain will be booted, --live requires a running domain
and lists current values, and --current queries according to the
current state of the domain (corresponding to --live if running, or
--config if inactive); these three flags are mutually exclusive.
Thus, this command always takes exactly zero or two flags.
vcpuinfo domain-id
Returns basic information about the domain virtual CPUs, like the
number of vCPUs, the running time, the affinity to physical
processors.
vcpupin domain-id [vcpu] [cpulist] [[--live] [--config] | [--current]]
Query or change the pinning of domain VCPUs to host physical CPUs.
To pin a single vcpu, specify cpulist; otherwise, you can query one
vcpu or omit vcpu to list all at once.
cpulist is a list of physical CPU numbers. Its syntax is a comma
separated list and a special markup using '-' and '^' (ex. '0-4',
'0-3,^2') can also be allowed. The '-' denotes the range and the
'^' denotes exclusive. If you want to reset vcpupin setting, that
is, to pin vcpu all physical cpus, simply specify 'r' as a cpulist.
If --live is specified, affect a running guest. If --config is
specified, affect the next boot of a persistent guest. If
--current is specified, affect the current guest state. Both
--live and --config flags may be given if cpulist is present, but
--current is exclusive. If no flag is specified, behavior is
different depending on hypervisor.
Note: The expression is sequentially evaluated, so "0-15,^8" is
identical to "9-14,0-7,15" but not identical to "^8,0-15".
vncdisplay domain-id
Output the IP address and port number for the VNC display. If the
information is not available the processes will provide an exit
code of 1.
DEVICE COMMANDS
The following commands manipulate devices associated to domains. The
domain-id can be specified as a short integer, a name or a full UUID.
To better understand the values allowed as options for the command
reading the documentation at <http://libvirt.org/formatdomain.html> on
the format of the device sections to get the most accurate set of
accepted values.
attach-device domain-id FILE
Attach a device to the domain, using a device definition in an XML
file. See the documentation to learn about libvirt XML format for
a device. For cdrom and floppy devices, this command only replaces
the media within the single existing device; consider using update-
device for this usage.
attach-disk domain-id source target [--driver driver] [--subdriver
subdriver] [--cache cache] [--type type] [--mode mode] [--persistent]
[--sourcetype soucetype] [--serial serial] [--shareable] [--address
address]
Attach a new disk device to the domain. source and target are
paths for the files and devices. driver can be file, tap or phy
for the Xen hypervisor depending on the kind of access; or qemu for
the QEMU emulator. type can indicate cdrom or floppy as
alternative to the disk default, although this use only replaces
the media within the existing virtual cdrom or floppy device;
consider using update-device for this usage instead. mode can
specify the two specific mode readonly or shareable. persistent
indicates the changes will affect the next boot of the domain.
sourcetype can indicate the type of source (block|file) cache can
be one of "default", "none", "writethrough", "writeback", or
"directsync". serial is the serial of disk device. shareable
indicates the disk device is shareable between domains. address is
the address of disk device in the form of
pci:domain.bus.slot.function, scsi:controller.bus.unit or
ide:controller.bus.unit.
attach-interface domain-id type source [--target target] [--mac mac]
[--script script] [--model model] [--persistent]
Attach a new network interface to the domain. type can be either
network to indicate a physical network device or bridge to indicate
a bridge to a device. source indicates the source device. target
allows to indicate the target device in the guest. mac allows to
specify the MAC address of the network interface. script allows to
specify a path to a script handling a bridge instead of the default
one. model allows to specify the model type. persistent indicates
the changes will affect the next boot of the domain.
detach-device domain-id FILE
Detach a device from the domain, takes the same kind of XML
descriptions as command attach-device.
detach-disk domain-id target
Detach a disk device from a domain. The target is the device as
seen from the domain.
detach-interface domain-id type [--mac mac]
Detach a network interface from a domain. type can be either
network to indicate a physical network device or bridge to indicate
a bridge to a device. It is recommended to use the mac option to
distinguish between the interfaces if more than one are present on
the domain.
update-device domain-id file [--persistent] [--force]
Update the characteristics of a device associated with domain-id,
based on the device definition in an XML file. If the --persistent
option is used, the changes will affect the next boot of the
domain. The --force option can be used to force device update,
e.g., to eject a CD-ROM even if it is locked/mounted in the domain.
See the documentation to learn about libvirt XML format for a
device.
VIRTUAL NETWORK COMMANDS
The following commands manipulate networks. Libvirt has the capability
to define virtual networks which can then be used by domains and linked
to actual network devices. For more detailed information about this
feature see the documentation at
<http://libvirt.org/formatnetwork.html> . Many of the commands for
virtual networks are similar to the ones used for domains, but the way
to name a virtual network is either by its name or UUID.
net-autostart network [--disable]
Configure a virtual network to be automatically started at boot.
The --disable option disable autostarting.
net-create file
Create a virtual network from an XML file, see the documentation to
get a description of the XML network format used by libvirt.
net-define file
Define a virtual network from an XML file, the network is just
defined but not instantiated.
net-destroy network
Destroy (stop) a given virtual network specified by its name or
UUID. This takes effect immediately.
net-dumpxml network
Output the virtual network information as an XML dump to stdout.
net-edit network
Edit the XML configuration file for a network.
This is equivalent to:
virsh net-dumpxml network > network.xml
vi network.xml (or make changes with your other text editor)
virsh net-define network.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
net-info network
Returns basic information about the network object.
net-list [--inactive | --all]
Returns the list of active networks, if --all is specified this
will also include defined but inactive networks, if --inactive is
specified only the inactive ones will be listed.
net-name network-UUID
Convert a network UUID to network name.
net-start network
Start a (previously defined) inactive network.
net-undefine network
Undefine the configuration for an inactive network.
net-uuid network-name
Convert a network name to network UUID.
INTERFACE COMMANDS
The following commands manipulate host interfaces. Often, these host
interfaces can then be used by name within domain <interface> elements
(such as a system-created bridge interface), but there is no
requirement that host interfaces be tied to any particular guest
configuration XML at all.
Many of the commands for host interfaces are similar to the ones used
for domains, and the way to name an interface is either by its name or
its MAC address. However, using a MAC address for an iface argument
only works when that address is unique (if an interface and a bridge
share the same MAC address, which is often the case, then using that
MAC address results in an error due to ambiguity, and you must resort
to a name instead).
iface-define file
Define a host interface from an XML file, the interface is just
defined but not started.
iface-destroy interface
Destroy (stop) a given host interface, such as by running "if-down"
to disable that interface from active use. This takes effect
immediately.
iface-dumpxml interface [--inactive]
Output the host interface information as an XML dump to stdout. If
--inactive is specified, then the output reflects the persistent
state of the interface that will be used the next time it is
started.
iface-edit interface
Edit the XML configuration file for a host interface.
This is equivalent to:
virsh iface-dumpxml iface > iface.xml
vi iface.xml (or make changes with your other text editor)
virsh iface-define iface.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
iface-list [--inactive | --all]
Returns the list of active host interfaces. If --all is specified
this will also include defined but inactive interfaces. If
--inactive is specified only the inactive ones will be listed.
iface-name interface
Convert a host interface MAC to interface name, if the MAC address
is unique among the host's interfaces.
interface specifies the interface MAC address.
iface-mac interface
Convert a host interface name to MAC address.
interface specifies the interface name.
iface-start interface
Start a (previously defined) host interface, such as by running
"if-up".
iface-undefine interface
Undefine the configuration for an inactive host interface.
iface-begin
Create a snapshot of current host interface settings, which can
later be committed (iface-commit) or restored (iface-rollback). If
a snapshot already exists, then this command will fail until the
previous snapshot has been committed or restored. Undefined
behavior results if any external changes are made to host
interfaces outside of the libvirt API between the beginning of a
snapshot and its eventual commit or rollback.
iface-commit
Declare all changes since the last iface-begin as working, and
delete the rollback point. If no interface snapshot has already
been started, then this command will fail.
iface-rollback
Revert all host interface settings back to the state recorded in
the last iface-begin. If no interface snapshot has already been
started, then this command will fail. Rebooting the host also
serves as an implicit rollback point.
STORAGE POOL COMMANDS
The following commands manipulate storage pools. Libvirt has the
capability to manage various storage solutions, including files, raw
partitions, and domain-specific formats, used to provide the storage
volumes visible as devices within virtual machines. For more detailed
information about this feature, see the documentation at
<http://libvirt.org/formatstorage.html> . Many of the commands for
pools are similar to the ones used for domains.
find-storage-pool-sources type [srcSpec]
Returns XML describing all storage pools of a given type that could
be found. If srcSpec is provided, it is a file that contains XML
to further restrict the query for pools.
find-storage-pool-sources-as type [host] [port] [initiator]
Returns XML describing all storage pools of a given type that could
be found. If host, port, or initiator are provided, they control
where the query is performed.
pool-autostart pool-or-uuid [--disable]
Configure whether pool should automatically start at boot.
pool-build pool-or-uuid [--overwrite] [--no-overwrite]
Build a given pool.
Options --overwrite and --no-overwrite can only be used for pool-
build a filesystem pool. If neither of them is specified, pool-
build on a filesystem pool only makes the directory; If
--no-overwrite is specified, it probes to determine if a filesystem
already exists on the target device, returning an error if exists,
or using mkfs to format the target device if not; If --overwrite is
specified, mkfs is always executed, any existed data on the target
device is overwritten unconditionally.
pool-create file
Create and start a pool object from the XML file.
pool-create-as name --print-xml type [source-host] [source-path]
[source-dev] [source-name] [<target>] [--source-format format]
Create and start a pool object name from the raw parameters. If
--print-xml is specified, then print the XML of the pool object
without creating the pool. Otherwise, the pool has the specified
type.
pool-define file
Create, but do not start, a pool object from the XML file.
pool-define-as name --print-xml type [source-host] [source-path]
[source-dev] [source-name] [<target>] [--source-format format]
Create, but do not start, a pool object name from the raw
parameters. If --print-xml is specified, then print the XML of the
pool object without defining the pool. Otherwise, the pool has the
specified type.
pool-destroy pool-or-uuid
Destroy (stop) a given pool object. Libvirt will no longer manage
the storage described by the pool object, but the raw data
contained in the pool is not changed, and can be later recovered
with pool-create.
pool-delete pool-or-uuid
Destroy the resources used by a given pool object. This operation
is non-recoverable. The pool object will still exist after this
command, ready for the creation of new storage volumes.
pool-dumpxml pool-or-uuid
Returns the XML information about the pool object.
pool-edit pool-or-uuid
Edit the XML configuration file for a storage pool.
This is equivalent to:
virsh pool-dumpxml pool > pool.xml
vi pool.xml (or make changes with your other text editor)
virsh pool-define pool.xml
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
pool-info pool-or-uuid
Returns basic information about the pool object.
pool-list [--inactive | --all] [--details]
List pool objects known to libvirt. By default, only pools in use
by active domains are listed; --inactive lists just the inactive
pools, and --all lists all pools. The --details option instructs
virsh to additionally display pool persistence and capacity related
information where available.
pool-name uuid
Convert the uuid to a pool name.
pool-refresh pool-or-uuid
Refresh the list of volumes contained in pool.
pool-start pool-or-uuid
Start the storage pool, which is previously defined but inactive.
pool-undefine pool-or-uuid
Undefine the configuration for an inactive pool.
pool-uuid pool
Returns the UUID of the named pool.
VOLUME COMMANDS
vol-create pool-or-uuid FILE
Create a volume from an XML <file>. pool-or-uuid is the name or
UUID of the storage pool to create the volume in. FILE is the XML
<file> with the volume definition. An easy way to create the XML
<file> is to use the vol-dumpxml command to obtain the definition
of a pre-existing volume.
Example
virsh vol-dumpxml --pool storagepool1 appvolume1 > newvolume.xml
vi newvolume.xml (or make changes with your other text editor)
virsh vol-create differentstoragepool newvolume.xml
vol-create-from pool-or-uuid FILE [--inputpool pool-or-uuid] vol-name-
or-key-or-path
Create a volume, using another volume as input. pool-or-uuid is
the name or UUID of the storage pool to create the volume in. FILE
is the XML <file> with the volume definition. --inputpool pool-or-
uuid is the name or uuid of the storage pool the source volume is
in. vol-name-or-key-or-path is the name or key or path of the
source volume.
vol-create-as pool-or-uuid name capacity [--allocation size] [--format
string] [--backing-vol vol-name-or-key-or-path] [--backing-vol-format
string]
Create a volume from a set of arguments. pool-or-uuid is the name
or UUID of the storage pool to create the volume in. name is the
name of the new volume. capacity is the size of the volume to be
created, with optional k, M, G, or T suffix. --allocation size is
the initial size to be allocated in the volume, with optional k, M,
G, or T suffix. --format string is used in file based storage
pools to specify the volume file format to use; raw, bochs, qcow,
qcow2, vmdk. --backing-vol vol-name-or-key-or-path is the source
backing volume to be used if taking a snapshot of an existing
volume. --backing-vol-format string is the format of the snapshot
backing volume; raw, bochs, qcow, qcow2, vmdk, host_device.
vol-clone [--pool pool-or-uuid] vol-name-or-key-or-path name
Clone an existing volume. Less powerful, but easier to type,
version of vol-create-from. --pool pool-or-uuid is the name or
UUID of the storage pool to create the volume in. vol-name-or-key-
or-path is the name or key or path of the source volume. name is
the name of the new volume.
vol-delete [--pool pool-or-uuid] vol-name-or-key-or-path
Delete a given volume. --pool pool-or-uuid is the name or UUID of
the storage pool the volume is in. vol-name-or-key-or-path is the
name or key or path of the volume to delete.
vol-upload [--pool pool-or-uuid] [--offset bytes] [--length bytes] vol-
name-or-key-or-path local-file
Upload the contents of local-file to a storage volume. --pool
pool-or-uuid is the name or UUID of the storage pool the volume is
in. vol-name-or-key-or-path is the name or key or path of the
volume to wipe. --offset is the position in the storage volume at
which to start writing the data. --length is an upper bound of the
amount of data to be uploaded. An error will occurr if the local-
file is greater than the specified length.
vol-download [--pool pool-or-uuid] [--offset bytes] [--length bytes]
vol-name-or-key-or-path local-file
Download the contents of local-file from a storage volume. --pool
pool-or-uuid is the name or UUID of the storage pool the volume is
in. vol-name-or-key-or-path is the name or key or path of the
volume to wipe. --offset is the position in the storage volume at
which to start reading the data. --length is an upper bound of the
amount of data to be downloaded.
vol-wipe [--pool pool-or-uuid] vol-name-or-key-or-path
Wipe a volume, ensure data previously on the volume is not
accessible to future reads. --pool pool-or-uuid is the name or UUID
of the storage pool the volume is in. vol-name-or-key-or-path is
the name or key or path of the volume to wipe.
vol-dumpxml [--pool pool-or-uuid] vol-name-or-key-or-path
Output the volume information as an XML dump to stdout. --pool
pool-or-uuid is the name or UUID of the storage pool the volume is
in. vol-name-or-key-or-path is the name or key or path of the
volume to output the XML of.
vol-info [--pool pool-or-uuid] vol-name-or-key-or-path
Returns basic information about the given storage volume. --pool
pool-or-uuid is the name or UUID of the storage pool the volume is
in. vol-name-or-key-or-path is the name or key or path of the
volume to return information for.
vol-list [--pool pool-or-uuid] [--details]
Return the list of volumes in the given storage pool. --pool pool-
or-uuid is the name or UUID of the storage pool. The --details
option instructs virsh to additionally display volume type and
capacity related information where available.
vol-pool [--uuid] vol-key-or-path
Return the pool name or UUID for a given volume. By default, the
pool name is returned. If the --uuid option is given, the pool UUID
is returned instead. vol-key-or-path is the key or path of the
volume to return the pool information for.
vol-path [--pool pool-or-uuid] vol-name-or-key
Return the path for a given volume. --pool pool-or-uuid is the
name or UUID of the storage pool the volume is in. vol-name-or-key
is the name or key of the volume to return the path for.
vol-name vol-key-or-path
Return the name for a given volume. vol-key-or-path is the key or
path of the volume to return the name for.
vol-key [--pool pool-or-uuid] vol-name-or-path
Return the volume key for a given volume. --pool pool-or-uuid is
the name or UUID of the storage pool the volume is in. vol-name-or-
path is the name or path of the volume to return the volume key
for.
SECRET COMMMANDS
The following commands manipulate "secrets" (e.g. passwords,
passphrases and encryption keys). Libvirt can store secrets
independently from their use, and other objects (e.g. volumes or
domains) can refer to the secrets for encryption or possibly other
uses. Secrets are identified using an UUID. See
<http://libvirt.org/formatsecret.html> for documentation of the XML
format used to represent properties of secrets.
secret-define file
Create a secret with the properties specified in file, with no
associated secret value. If file does not specify a UUID, choose
one automatically. If file specifies an UUID of an existing
secret, replace its properties by properties defined in file,
without affecting the secret value.
secret-dumpxml secret
Output properties of secret (specified by its UUID) as an XML dump
to stdout.
secret-set-value secret base64
Set the value associated with secret (specified by its UUID) to the
value Base64-encoded value base64.
secret-get-value secret
Output the value associated with secret (specified by its UUID) to
stdout, encoded using Base64.
secret-undefine secret
Delete a secret (specified by its UUID), including the associated
value, if any.
secret-list
Output a list of UUIDs of known secrets to stdout.
SNAPSHOT COMMMANDS
The following commands manipulate domain snapshots. Snapshots take the
disk, memory, and device state of a domain at a point-of-time, and save
it for future use. They have many uses, from saving a "clean" copy of
an OS image to saving a domain's state before a potentially destructive
operation. Snapshots are identified with a unique name. See
<http://libvirt.org/formatsnapshot.html> for documentation of the XML
format used to represent properties of snapshots.
snapshot-create domain [xmlfile] {[--redefine [--current]] |
[--no-metadata] [--halt] [--disk-only]}
Create a snapshot for domain domain with the properties specified
in xmlfile. Normally, the only properties settable for a domain
snapshot are the <name> and <description> elements, as well as
<disks> if --disk-only is given; the rest of the fields are
ignored, and automatically filled in by libvirt. If xmlfile is
completely omitted, then libvirt will choose a value for all
fields. The new snapshot will become current, as listed by
snapshot-current.
If --halt is specified, the domain will be left in an inactive
state after the snapshot is created.
If --disk-only is specified, the snapshot will only include disk
state rather than the usual system checkpoint with vm state. Disk
snapshots are faster than full system checkpoints, but reverting to
a disk snapshot may require fsck or journal replays, since it is
like the disk state at the point when the power cord is abruptly
pulled; and mixing --halt and --disk-only loses any data that was
not flushed to disk at the time.
If --redefine is specified, then all XML elements produced by
snapshot-dumpxml are valid; this can be used to migrate snapshot
hierarchy from one machine to another, to recreate hierarchy for
the case of a transient domain that goes away and is later
recreated with the same name and UUID, or to make slight
alterations in the snapshot metadata (such as host-specific aspects
of the domain XML embedded in the snapshot). When this flag is
supplied, the xmlfile argument is mandatory, and the domain's
current snapshot will not be altered unless the --current flag is
also given.
If --no-metadata is specified, then the snapshot data is created,
but any metadata is immediately discarded (that is, libvirt does
not treat the snapshot as current, and cannot revert to the
snapshot unless --redefine is later used to teach libvirt about the
metadata again).
Existence of snapshot metadata will prevent attempts to undefine a
persistent domain. However, for transient domains, snapshot
metadata is silently lost when the domain quits running (whether by
command such as destroy or by internal guest action).
snapshot-create-as domain {[--print-xml] | [--no-metadata] [--halt]}
[name] [description] [--disk-only [[--diskspec] diskspec]...
Create a snapshot for domain domain with the given <name> and
<description>; if either value is omitted, libvirt will choose a
value. If --print-xml is specified, then XML appropriate for
snapshot-create is output, rather than actually creating a
snapshot. Otherwise, if --halt is specified, the domain will be
left in an inactive state after the snapshot is created, and if
--disk-only is specified, the snapshot will not include vm state.
The --disk-only flag is used to request a disk-only snapshot. When
this flag is in use, the command can also take additional diskspec
arguments to add <disk> elements to the xml. Each <diskspec> is in
the form disk[,snapshot=type][,driver=type][,file=name]. To
include a literal comma in disk or in file=name, escape it with a
second comma. A literal --diskspec must preceed each diskspec
unless all three of domain, name, and description are also present.
For example, a diskspec of
"vda,snapshot=external,file=/path/to,,new" results in the following
XML:
<disk name='vda' snapshot='external'>
<source file='/path/to,new'/>
</disk>
If --no-metadata is specified, then the snapshot data is created,
but any metadata is immediately discarded (that is, libvirt does
not treat the snapshot as current, and cannot revert to the
snapshot unless snapshot-create is later used to teach libvirt
about the metadata again). This flag is incompatible with
--print-xml.
snapshot-current domain {[--name] | [--security-info] | [snapshotname]}
Without snapshotname, this will output the snapshot XML for the
domain's current snapshot (if any). If --name is specified, just
the current snapshot name instead of the full xml. Otherwise,
using --security-info will also include security sensitive
information in the XML.
With snapshotname, this is a request to make the existing named
snapshot become the current snapshot, without reverting the domain.
snapshot-edit domain snapshotname [--current]
Edit the XML configuration file for snapshotname of a domain. If
--current is specified, also force the edited snapshot to become
the current snapshot.
This is equivalent to:
virsh snapshot-dumpxml dom name > snapshot.xml
vi snapshot.xml (or make changes with your other text editor)
virsh snapshot-create dom snapshot.xml --redefine [--current]
except that it does some error checking.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
snapshot-list domain [{--parent | --roots}] [--metadata]
List all of the available snapshots for the given domain.
If --parent is specified, add a column to the output table giving
the name of the parent of each snapshot.
If --roots is specified, the list will be filtered to just
snapshots that have no parents; this option is not compatible with
--parent.
If --metadata is specified, the list will be filtered to just
snapshots that involve libvirt metadata, and thus would prevent
undefine of a persistent domain, or be lost on destroy of a
transient domain.
snapshot-dumpxml domain snapshot [--security-info]
Output the snapshot XML for the domain's snapshot named snapshot.
Using --security-info will also include security sensitive
information.
snapshot-parent domain snapshot
Output the name of the parent snapshot for the given snapshot, if
any.
snapshot-revert domain snapshot [{--running | --paused}]
Revert the given domain to the snapshot specified by snapshot. Be
aware that this is a destructive action; any changes in the domain
since the last snapshot was taken will be lost. Also note that the
state of the domain after snapshot-revert is complete will be the
state of the domain at the time the original snapshot was taken.
Normally, reverting to a snapshot leaves the domain in the state it
was at the time the snapshot was created, except that a disk
snapshot with no vm state leaves the domain in an inactive state.
Passing either the --running or --paused flag will perform
additional state changes (such as booting an inactive domain, or
pausing a running domain). Since transient domains cannot be
inactive, it is required to use one of these flags when reverting
to a disk snapshot of a transient domain.
snapshot-delete domain snapshot [--metadata] [{--children |
--children-only}]
Delete the snapshot for the domain named snapshot. If this
snapshot has child snapshots, changes from this snapshot will be
merged into the children. If --children is passed, then delete
this snapshot and any children of this snapshot. If
--children-only is passed, then delete any children of this
snapshot, but leave this snapshot intact. These two flags are
mutually exclusive.
If --metadata is specified, then only delete the snapshot metadata
maintained by libvirt, while leaving the snapshot contents intact
for access by external tools; otherwise deleting a snapshot also
removes the data contents from that point in time.
NWFILTER COMMMANDS
The following commands manipulate network filters. Network filters
allow filtering of the network traffic coming from and going to virtual
machines. Individual network traffic filters are written in XML and
may contain references to other network filters, describe traffic
filtering rules, or contain both. Network filters are referenced by
virtual machines from within their interface description. A network
filter may be referenced by multiple virtual machines' interfaces.
nwfilter-define xmlfile
Make a new network filter known to libvirt. If a network filter
with the same name already exists, it will be replaced with the new
XML. Any running virtual machine referencing this network filter
will have its network traffic rules adapted. If for any reason the
network traffic filtering rules cannot be instantiated by any of
the running virtual machines, then the new XML will be rejected.
nwfilter-undefine nwfilter-name
Delete a network filter. The deletion will fail if any running
virtual machine is currently using this network filter.
nwfilter-list
List all of the available network filters.
nwfilter-dumpxml nwfilter-name
Output the network filter XML.
nwfilter-edit nwfilter-name
Edit the XML of a network filter.
This is equivalent to:
virsh nwfilter-dumpxml myfilter > myfilter.xml
vi myfilter.xml (or make changes with your other text editor)
virsh nwfilter-define myfilter.xml
except that it does some error checking. The new network filter
may be rejected due to the same reason as mentioned in nwfilter-
define.
The editor used can be supplied by the $VISUAL or $EDITOR
environment variables, and defaults to "vi".
QEMU-SPECIFIC COMMANDS
NOTE: Use of the following commands is strongly discouraged. They can
cause libvirt to become confused and do the wrong thing on subsequent
operations. Once you have used this command, please do not report
problems to the libvirt developers; the reports will be ignored.
qemu-attach pid
Attach an externally launched QEMU process to the libvirt QEMU
driver. The QEMU process must have been created with a monitor
connection using the UNIX driver. Ideally the process will also
have had the '-name' argument specified.
$ qemu-kvm -cdrom ~/demo.iso \
-monitor unix:/tmp/demo,server,nowait \
-name foo \
-uuid cece4f9f-dff0-575d-0e8e-01fe380f12ea &
$ QEMUPID=$!
$ virsh qemu-attach $QEMUPID
Not all functions of libvirt are expected to work reliably after
attaching to an externally launched QEMU process. There may be
issues with the guest ABI changing upon migration, and hotunplug
may not work.
qemu-monitor-command domain [--hmp] command...
Send an arbitrary monitor command command to domain domain through
the qemu monitor. The results of the command will be printed on
stdout. If --hmp is passed, the command is considered to be a
human monitor command and libvirt will automatically convert it
into QMP if needed. In that case the result will also be converted
back from QMP. If more than one argument is provided for command,
they are concatenated with a space in between before passing the
single command to the monitor.
ENVIRONMENT
The following environment variables can be set to alter the behaviour
of "virsh"
VIRSH_DEBUG=<0 to 4>
Turn on verbose debugging of virsh commands. Valid levels are
* VIRSH_DEBUG=0
DEBUG - Messages at ALL levels get logged
* VIRSH_DEBUG=1
INFO - Logs messages at levels INFO, NOTICE, WARNING and ERROR
* VIRSH_DEBUG=2
NOTICE - Logs messages at levels NOTICE, WARNING and ERROR
* VIRSH_DEBUG=3
WARNING - Logs messages at levels WARNING and ERROR
* VIRSH_DEBUG=4
ERROR - Messages at only ERROR level gets logged.
VIRSH_LOG_FILE="LOGFILE"
The file to log virsh debug messages.
VIRSH_DEFAULT_CONNECT_URI
The hypervisor to connect to by default. Set this to a URI, in the
same format as accepted by the connect option.
VISUAL
The editor to use by the edit and related options.
EDITOR
The editor to use by the edit and related options, if "VISUAL" is
not set.
LIBVIRT_DEBUG=LEVEL
Turn on verbose debugging of all libvirt API calls. Valid levels
are
· LIBVIRT_DEBUG=1
Messages at level DEBUG or above
· LIBVIRT_DEBUG=2
Messages at level INFO or above
· LIBVIRT_DEBUG=3
Messages at level WARNING or above
· LIBVIRT_DEBUG=4
Messages at level ERROR or above
For further information about debugging options consult
"http://libvirt.org/logging.html"
BUGS
Report any bugs discovered to the libvirt community via the mailing
list "http://libvirt.org/contact.html" or bug tracker
"http://libvirt.org/bugs.html". Alternatively report bugs to your
software distributor / vendor.
AUTHORS
Please refer to the AUTHORS file distributed with libvirt.
Based on the xm man page by:
Sean Dague <sean at dague dot net>
Daniel Stekloff <dsteklof at us dot ibm dot com>
COPYRIGHT
Copyright (C) 2005, 2007-2010 Red Hat, Inc., and the authors listed in
the libvirt AUTHORS file.
LICENSEvirsh is distributed under the terms of the GNU LGPL v2+. This is free
software; see the source for copying conditions. There is NO warranty;
not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
SEE ALSOvirt-install(1), virt-xml-validate(1), virt-top(1), virt-df(1),
<http://www.libvirt.org/>
POD ERRORS
Hey! The above document had some coding errors, which are explained
below:
Around line 1090:
Unterminated I<...> sequence
Around line 1827:
Unterminated I<...> sequence
libvirt-0.9.6.4 2013-01-28 VIRSH(1)
