=head1 NAME virsh - management user interface =head1 SYNOPSIS virsh [args] =head1 DESCRIPTION The B 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, OpenNebula, and VMware ESX. The basic structure of most virsh usage is: virsh [OPTIONS] Where I is one of the commands listed below, I is the numeric domain id, or the domain name (which will be internally translated to domain id), and I 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 B program can be used either to run one command at a time by giving the command as an argument on the command line, or as a shell if no command is given in the command line, it will then start a minimal interpreter waiting for your commands and the B command will then exit the program. =head1 NOTES Most B operations rely upon the libvirt library being able to connect to an already running libvirtd service. This can usually be done using the command B. Most B 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 B commands act synchronously, except maybe shutdown, setvcpus and setmem. In those cases the fact that the B program returned, may not mean the action is complete and you must poll periodically to detect that the guest completed the operation. =head1 GENERIC COMMANDS The following commands are generic i.e. not specific to a domain. =over 4 =item B optional I This prints a small synopsis about all commands available for B B I will print out a detailed help message on that command. =item B, B quit this interactive terminal =item B Will print out the major version info about what this built from. =over 4 B B 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 =back =item B optional I Will change current directory to I. The default directory for the B command is the home directory or, if there is no I variable in the environment, the root directory. This command is only available in interactive mode. =item B Will print the current directory. =item B I optional I<--readonly> (Re)-Connect to the hypervisor. When the shell is first started, this is automatically run with the I parameter requested by the C<-c> option on the command line. The I parameter specifies how to connect to the hypervisor. The documentation page at L list the values supported, but the most common are: =over 4 =item xen:/// this is used to connect to the local Xen hypervisor, this is the default =item qemu:///system connect locally as root to the daemon supervising QEmu and KVM domains =item qemu:///session connect locally as a normal user to his own set of QEmu and KVM domains =item lxc:/// connect to a local linux container =back For remote access see the documentation page on how to make URIs. The I<--readonly> option allows for read-only connection =item B Prints the hypervisor canonical URI, can be useful in shell mode. =item B Print the hypervisor hostname. =item B Returns basic information about the node, like number and type of CPU, and size of the physical memory. =item B 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: L The XML also show the NUMA topology information if available. =item B optional I<--inactive> I<--all> Prints information about one or more domains. If no domains are specified it prints out information about running domains. An example format for the list is as follows: B 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). B The State field lists 7 states for a domain, and which ones the current domain is in. =over 4 =item B The domain is currently running on a CPU =item B 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. =item B The domain has been paused, usually occurring through the administrator running B. When in a paused state the domain will still consume allocated resources like memory, but will not be eligible for scheduling by the hypervisor. =item B 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. =item B The domain is not running. Usually this indicates the domain has been shut down completely, or has not been started. =item B 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. =item B The domain is in process of dying, but hasn't completely shutdown or crashed. =back =item B optional I Prints the available amount of memory on the machine or within a NUMA cell if I is provided. =item B I Compute baseline CPU which will be supported by all host CPUs given in . The list of host CPUs is built by extracting all elements from the . Thus, the can contain either a set of elements separated by new lines or even a set of complete elements printed by B command. =item B I Compare CPU definition from XML with host CPU. The XML may contain either host or guest CPU definition. The host CPU definition is the element and its contents as printed by B command. The guest CPU definition is the element and its contents from domain XML definition. For more information on guest CPU definition see: L =back =head1 DOMAIN COMMANDS The following commands manipulate domains directly, as stated previously most commands take domain-id as the first parameter. The I can be specified as an short integer, a name or a full UUID. =over 4 =item B optional I<--disable> I Configure a domain to be automatically started at boot. The option I<--disable> disables autostarting. =item B I Connect the virtual serial console for the guest. =item B I optional I<--console> I<--paused> Create a domain from an XML . An easy way to create the XML is to use the B command to obtain the definition of a pre-existing guest. The domain will be paused if the I<--paused> option is used and supported by the driver; otherwise it will be running. If I<--console> is requested, attach to the console after creation. B virsh dumpxml > domain.xml edit domain.xml virsh create < domain.xml =item B I Define a domain from an XML . The domain definition is registered but not started. =item B I 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 B command instead. =item B I I Get device block stats for a running domain. =item B I I Get network interface stats for a running domain. =item B I Get memory stats for a running domain. =item B I I Get block device size info for a domain. =item B I Returns basic information about the domain. =item B I Convert a domain name or id to domain UUID =item B I Convert a domain name (or UUID) to a domain id =item B I Abort the currently running domain job. =item B I Returns information about jobs running on a domain. =item B I Convert a domain Id (or UUID) to domain name =item B I Returns state about a running domain. =item B I I Convert the file I in the native guest configuration format named by I to a domain XML format. =item B I I Convert the file I in domain XML format to the native guest configuration format named by I. =item B I I Dumps the core of a domain to a file for analysis. =item B I optional I<--inactive> I<--security-info> I<--update-cpu> Output the domain information as an XML dump to stdout, this format can be used by the B command. Additional options affecting the XML dump may be used. I<--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 I<--security-info> security sensitive information will also be included in the XML dump. I<--update-cpu> updates domain CPU requirements according to host CPU. =item B I Edit the XML configuration file for a domain. This is equivalent to: virsh dumpxml domain > domain.xml edit domain.xml virsh define domain.xml except that it does some error checking. The editor used can be supplied by the C<$VISUAL> or C<$EDITOR> environment variables, and defaults to C. =item B I Ask libvirt to save a running domain state in a place managed by libvirt. If libvirt is asked to restart the domain later on it will resume it from the saved domain state (and the state is discarded). =item B I Remove the managed save file for a domain if it exists. The next time the domain is started it will not restore to its previous state but instead will do a full boot. =item B optional I<--live> I<--suspend> I I I Migrate domain to another host. Add --live for live migration; --suspend leaves the domain paused on the destination host. The I is the connection URI of the destination host, and I is the migration URI, which usually can be omitted. =item B I I Set maximum tolerable downtime for a domain which is being live-migrated to another host. The I is a number of milliseconds the guest is allowed to be down at the end of live migration. =item B I Reboot a domain. This acts just as if the domain had the B 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 I parameter in the domain's XML definition. =item B I Restores a domain from an B state file. See I for more info. =item B I I Saves a running domain 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. B restores from this state file. 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. =item B optional I<--set> B I =item B optional I<--weight> B optional I<--cap> B I Allows you to show (and set) the domain scheduler parameters. The parameters available for each hypervisor are: LXC, QEMU/KVM (posix scheduler): cpu_shares Xen (credit scheduler): weight, cap ESX (allocation scheduler): reservation, limit, shares B: The cpu_shares parameter has a valid value range of 0-262144. B: The weight and cap parameters are defined only for the XEN_CREDIT scheduler and are now I. =item B I B Change the current memory allocation in the guest domain. This should take effect immediately. The memory limit is specified in kilobytes. For Xen, you can only adjust the memory of a running domain if the domain is paravirtualized or running the PV balloon driver. =item B I B Change the maximum memory allocation limit in the guest domain. This should not change the current memory use. The memory limit is specified in kilobytes. =item B I I Change the number of virtual CPUs active in the guest domain. Note that I may be limited by host, hypervisor or limit coming from the original description of domain. For Xen, you can only adjust the virtual CPUs of a running domain if the domain is paravirtualized. =item B I 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 I parameter in the domain's XML definition. =item B I optional I<--console> I<--paused> Start a (previously defined) inactive domain. The domain will be paused if the I<--paused> option is used and supported by the driver; otherwise it will be running. If I<--console> is requested, attach to the console after creation. =item B I Suspend a running domain. It is kept in memory but won't be scheduled anymore. =item B I 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. =item B I 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. =item B I Undefine the configuration for an inactive domain. Since it's not running the domain name or UUID must be used as the I. =item B I Returns basic information about the domain virtual CPUs, like the number of vCPUs, the running time, the affinity to physical processors. =item B I I I Pin domain VCPUs to host physical CPUs. The I number must be provided and I is a comma separated list of physical CPU numbers. =item B I 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. =back =head1 DEVICE COMMANDS The following commands manipulate devices associated to domains. The domain-id can be specified as an short integer, a name or a full UUID. To better understand the values allowed as options for the command reading the documentation at L on the format of the device sections to get the most accurate set of accepted values. =over 4 =item B I I 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 B for this usage. =item B I I I optional I<--driver driver> I<--subdriver subdriver> I<--type type> I<--mode mode> Attach a new disk device to the domain. I and I are paths for the files and devices. I can be I, I or I depending on the kind of access. I can indicate I or I as alternative to the disk default, although this use only replaces the media within the existing virtual cdrom or floppy device; consider using B for this usage instead. I can specify the two specific mode I or I. =item B I I I optional I<--target target> I<--mac mac> I<--script script> Attach a new network interface to the domain. I can be either I to indicate a physical network device or I to indicate a bridge to a device. I indicates the source device. I allows to indicate the target device in the guest. I allows to specify the MAC address of the network interface. I