7 Managing A KVM Guest From The Command Line
CentOS 6.3 KVM Host:
KVM guests can be managed through virsh, the "virtual shell". To connect to the virtual shell, run
virsh --connect qemu:///system
This is how the virtual shell looks:
[root@server1 ~]# virsh --connect qemu:///system
Welcome to virsh, the virtualization interactive terminal.
Type: 'help' for help with commands
'quit' to quit
virsh #
You can now type in commands on the virtual shell to manage your guests. Run
help
to get a list of available commands:
virsh # help
Grouped commands:
Domain Management (help keyword 'domain'):
attach-device attach device from an XML file
attach-disk attach disk device
attach-interface attach network interface
autostart autostart a domain
blkiotune Get or set blkio parameters
blockpull Populate a disk from its backing image.
blockjob Manage active block operations.
console connect to the guest console
cpu-baseline compute baseline CPU
cpu-compare compare host CPU with a CPU described by an XML file
create create a domain from an XML file
define define (but don't start) a domain from an XML file
destroy destroy (stop) a domain
detach-device detach device from an XML file
detach-disk detach disk device
detach-interface detach network interface
domid convert a domain name or UUID to domain id
domjobabort abort active domain job
domjobinfo domain job information
domname convert a domain id or UUID to domain name
domuuid convert a domain name or id to domain UUID
domxml-from-native Convert native config to domain XML
domxml-to-native Convert domain XML to native config
dump dump the core of a domain to a file for analysis
dumpxml domain information in XML
edit edit XML configuration for a domain
inject-nmi Inject NMI to the guest
send-key Send keycodes to the guest
managedsave managed save of a domain state
managedsave-remove Remove managed save of a domain
maxvcpus connection vcpu maximum
memtune Get or set memory parameters
migrate migrate domain to another host
migrate-setmaxdowntime set maximum tolerable downtime
migrate-setspeed Set the maximum migration bandwidth
reboot reboot a domain
restore restore a domain from a saved state in a file
resume resume a domain
save save a domain state to a file
save-image-define redefine the XML for a domain's saved state file
save-image-dumpxml saved state domain information in XML
save-image-edit edit XML for a domain's saved state file
schedinfo show/set scheduler parameters
screenshot take a screenshot of a current domain console and store it into a file
setmaxmem change maximum memory limit
setmem change memory allocation
setvcpus change number of virtual CPUs
shutdown gracefully shutdown a domain
start start a (previously defined) inactive domain
suspend suspend a domain
ttyconsole tty console
undefine undefine an inactive domain
update-device update device from an XML file
vcpucount domain vcpu counts
vcpuinfo detailed domain vcpu information
vcpupin control or query domain vcpu affinity
version show version
vncdisplay vnc display
Domain Monitoring (help keyword 'monitor'):
domblkinfo domain block device size information
domblklist list all domain blocks
domblkstat get device block stats for a domain
domcontrol domain control interface state
domifstat get network interface stats for a domain
dominfo domain information
dommemstat get memory statistics for a domain
domstate domain state
list list domains
Host and Hypervisor (help keyword 'host'):
capabilities capabilities
connect (re)connect to hypervisor
freecell NUMA free memory
hostname print the hypervisor hostname
nodecpustats Prints cpu stats of the node.
nodeinfo node information
nodememstats Prints memory stats of the node.
qemu-attach QEMU Attach
qemu-monitor-command QEMU Monitor Command
sysinfo print the hypervisor sysinfo
uri print the hypervisor canonical URI
Interface (help keyword 'interface'):
iface-begin create a snapshot of current interfaces settings, which can be later commited (iface-commit) or restored (iface-rollback)
iface-commit commit changes made since iface-begin and free restore point
iface-define define (but don't start) a physical host interface from an XML file
iface-destroy destroy a physical host interface (disable it / "if-down")
iface-dumpxml interface information in XML
iface-edit edit XML configuration for a physical host interface
iface-list list physical host interfaces
iface-mac convert an interface name to interface MAC address
iface-name convert an interface MAC address to interface name
iface-rollback rollback to previous saved configuration created via iface-begin
iface-start start a physical host interface (enable it / "if-up")
iface-undefine undefine a physical host interface (remove it from configuration)
Network Filter (help keyword 'filter'):
nwfilter-define define or update a network filter from an XML file
nwfilter-dumpxml network filter information in XML
nwfilter-edit edit XML configuration for a network filter
nwfilter-list list network filters
nwfilter-undefine undefine a network filter
Networking (help keyword 'network'):
net-autostart autostart a network
net-create create a network from an XML file
net-define define (but don't start) a network from an XML file
net-destroy destroy (stop) a network
net-dumpxml network information in XML
net-edit edit XML configuration for a network
net-info network information
net-list list networks
net-name convert a network UUID to network name
net-start start a (previously defined) inactive network
net-undefine undefine an inactive network
net-uuid convert a network name to network UUID
Node Device (help keyword 'nodedev'):
nodedev-create create a device defined by an XML file on the node
nodedev-destroy destroy (stop) a device on the node
nodedev-dettach dettach node device from its device driver
nodedev-dumpxml node device details in XML
nodedev-list enumerate devices on this host
nodedev-reattach reattach node device to its device driver
nodedev-reset reset node device
Secret (help keyword 'secret'):
secret-define define or modify a secret from an XML file
secret-dumpxml secret attributes in XML
secret-get-value Output a secret value
secret-list list secrets
secret-set-value set a secret value
secret-undefine undefine a secret
Snapshot (help keyword 'snapshot'):
snapshot-create Create a snapshot from XML
snapshot-create-as Create a snapshot from a set of args
snapshot-current Get or set the current snapshot
snapshot-delete Delete a domain snapshot
snapshot-dumpxml Dump XML for a domain snapshot
snapshot-edit edit XML for a snapshot
snapshot-list List snapshots for a domain
snapshot-parent Get the name of the parent of a snapshot
snapshot-revert Revert a domain to a snapshot
Storage Pool (help keyword 'pool'):
find-storage-pool-sources-as find potential storage pool sources
find-storage-pool-sources discover potential storage pool sources
pool-autostart autostart a pool
pool-build build a pool
pool-create-as create a pool from a set of args
pool-create create a pool from an XML file
pool-define-as define a pool from a set of args
pool-define define (but don't start) a pool from an XML file
pool-delete delete a pool
pool-destroy destroy (stop) a pool
pool-dumpxml pool information in XML
pool-edit edit XML configuration for a storage pool
pool-info storage pool information
pool-list list pools
pool-name convert a pool UUID to pool name
pool-refresh refresh a pool
pool-start start a (previously defined) inactive pool
pool-undefine undefine an inactive pool
pool-uuid convert a pool name to pool UUID
Storage Volume (help keyword 'volume'):
vol-clone clone a volume.
vol-create-as create a volume from a set of args
vol-create create a vol from an XML file
vol-create-from create a vol, using another volume as input
vol-delete delete a vol
vol-download Download a volume to a file
vol-dumpxml vol information in XML
vol-info storage vol information
vol-key returns the volume key for a given volume name or path
vol-list list vols
vol-name returns the volume name for a given volume key or path
vol-path returns the volume path for a given volume name or key
vol-pool returns the storage pool for a given volume key or path
vol-upload upload a file into a volume
vol-wipe wipe a vol
Virsh itself (help keyword 'virsh'):
cd change the current directory
echo echo arguments
exit quit this interactive terminal
help print help
pwd print the current directory
quit quit this interactive terminal
virsh #
list
shows all running guests;
list --all
shows all guests, running and inactive:
virsh # list --all
Id Name State
----------------------------------
3 vm11 running
- vm10 shut off
virsh #
If you modify a guest's xml file (located in the /etc/libvirt/qemu/ directory), you must redefine the guest:
define /etc/libvirt/qemu/vm10.xml
Please note that whenever you modify the guest's xml file in /etc/libvirt/qemu/, you must run the define command again!
To start a stopped guest, run:
start vm10
To stop a guest, run
shutdown vm10
To immediately stop it (i.e., pull the power plug), run
destroy vm10
Suspend a guest:
suspend vm10
Resume a guest:
resume vm10
These are the most important commands.
Type
quit
to leave the virtual shell.
Virtualization With KVM On A CentOS 6.3 Server - Page 4