Novell Doc: Virtualization: Configuration Options and Settings

1.1 xm Commands

The xm command provides a command line interface for managing virtual machines. It can be used to create, pause, and shut down virtual machines. It can also be used to list the current domains, enable or pin virtual CPUs, and attach or detach block devices. For example, the xm list command displays the status of all virtual machines.

Figure 1-1 xm list Command

The syntax of the xm command usually follows the format:

xm  <subcommand> [domain-id] [OPTIONS]

where subcommand is the xm command to run, domain-id is the ID number assigned to a domain or the name of the virtual machine, and OPTIONS indicates subcommand-specific options.

All xm operations require that the Xen control daemon, xend, be running. For this reason, you should make sure xend starts whenever the host boots.
Most xm commands require root privileges to allow interaction with the Xen hypervisor. Entering the xm command as a user other than root returns an error.
Some xm commands return no information even though the action is completed. In some instances, for example, when shutting down a virtual machine, the action can take several seconds to complete. To verify that the action has completed, you might need to view its status another way, such as, using the xm list command.

Table 1-1 xm Subcommands

xm Subcommand	Description
help	Displays the list of xm subcommands
console	Attaches to a domain’s console (Paravirtual only). Virtual machines do not support more than one console connection at a time.
create	Start a new domain using settings from a configuration file. (Deprecated: use xm new)
new	Add a domain to the xend database. xm new -f to specify a configuration file based on Python*. xm new -F to specify an .sxp configuration file
delete	Removes a domain from xend domain management.
destroy	Terminates a domain immediately.
domid	Converts a domain name to domain ID.
domname	Converts a domain ID to a domain name.
dump-core	Dumps a core for a specific domain.
list	Lists information about some or all domains.
mem-max	Sets the maximum amount of memory to reserve for a domain.
mem-set	Sets the current amount of memory usage for a domain.
migrate	Migrates a domain to another host.
pause	Pauses a domain but maintain its current state in memory.
reboot	Reboots a domain.
rename	Renames a domain.
restore	Restores a domain from a saved state.
resume	Resumes a suspended domain.
save	Saves a domain’s entire state, including disk and memory, to a file.
shutdown	Shuts down a domain.
start	Starts a xend managed domain.
suspend	Saves a domain’s current state.
sysrq	Sends a sysrq to a domain.
top	Monitors a host and domains in real time.
unpause	Unpauses a paused domain.
uptime	Prints uptime for a domain.
vcpu-list	Lists the virtual CPUs for a domain or all domains.
vcpu-pin	Specifies which CPUs a virtual CPU can use.
vcpu-set	Sets the number of active virtual CPUs allowed for the domain.
dmesg	Reads and/or clears the xend message buffer.
info	Gets information about the Xen host environment.
log	Prints xend log file.
serve	Proxies xend XMLRPC over stdio.
sched-credit	Gets or sets credit scheduler parameters.
sched-sedf	Gets or sets EDF parameters.
block-attach	Creates a new virtual block device.
block-detach	Destroys a domain’s virtual block device.
block-list	Lists virtual block devices for a domain.
block-configure	Changes block device configuration.
network-attach	Creates a new virtual network device and attach to it.
network-detach	Detaches a domain’s virtual network device.
network-list	Lists virtual network interfaces for a domain.
vtpm-list	Lists virtual TPM devices.
vnet-list	Lists vnets.
vnet-create	Creates a vnet from a configuration file.
vnet-delete	Deletes a vnet.
labels	Lists <type> labels for (active) policy.
addlabel	Adds a security label for domain or resource.
rmlabel	Removes a security label for domain or resource.
getlabel	Shows a security label for domain or resource.
dry-run	Tests if a domain can access its resources.
resources	Shows information for each labeled resource.
makepolicy	Builds a policy and creates .bin and .map files.
loadpolicy	Loads a binary policy into the hypervisor.
cfgbootpolicy	Adds a policy to the boot configuration.
dumppolicy	Prints hypervisor ACM state information.
shell	Launches an interactive shell.