Virsh

connect URIs

virsh -c qemu+ssh://dapple/system list --all

Storage

Create storagepool

Create LVM pool:

virsh pool-define-as libvirt logical --source-name dapple-vg --target /dev/mapper/system_crypt
virsh pool-autostart libvirt

Edit files inside a shutdown VM from the host

virt-edit baseimage.dfi.local /etc/default/grub

rename machine

virsh dumpxml name_of_vm > /tmp/name_of_vm.xml

Undefine the old vm to prevent an error because of an duplicate UUID.

virsh undefine name-of-vm

Edit the xml file then import it.

virsh define /tmp/name_of_vm.xml

List / dominfo

virsh list --all
virsh dominfo debian-vpn

Show all domains memory:

virsh domstats --balloon
virsh domstats --balloon |grep -E '(Domain|balloon.max)'

Modify VMs

Add memory

export DOM=dapple-media-controlplane

virsh dominfo $DOM | grep memory
virsh shutdown $DOM
virsh setmaxmem $DOM 12G --config
virsh setmem $DOM 12G --config
virsh start $DOM

Add a vCPU

See Modifying the number of virtual CPUs

virsh vcpucount $DOM
virsh shutdown $DOM
virsh setvcpus $DOM 3 --maximum --config
virsh setvcpus $DOM 3 --config
virsh start $DOM

Modify description

virsh desc --config --new-desc "K3s agent: Gitlab agent and runner, tym-flow CI and prod deployment" $DOM
virsh desc --current --new-desc "K3s agent: Gitlab agent and runner, tym-flow CI and prod deployment" $DOM

Modify auto-start behaviour

Enable autostart:

$ virsh autostart $DOM
Domain '$DOM' marked as autostarted

Disable autostart:

$ virsh autostart --disable jump
Domain 'jump' unmarked as autostarted

List domains marked as autostart:

virsh list --autostart --all

Add a data disk to existing domain

virsh vol-create-as <POOL>  <NAME> 12G --format qcow2 --allocation 30G

qcow2:

virsh vol-create-as virtimages try.pixelated-project.org.data.img 14G --format qcow2 --allocation 14G
virsh attach-disk try.pixelated-project.org \
  --source /var/lib/libvirt/images/try.pixelated-project.org.data.img \
  --target vdb --persistent

lvm:

virsh vol-create-as lvm try.pixelated-project.org.data.img 20G
virsh attach-disk try.pixelated-project.org --source /dev/n097h049/try.pixelated-project.org.data.img --target vdb --persistent

virsh detach-disk try.pixelated-project.org --target vdb
virsh vol-delete --pool virtimages try.pixelated-project.org.data.img

Remove domain

virsh undefine --managed-save --remove-all-storage DOMAIN

Find IP of VM

Oneliner:

 for mac in `virsh domiflist platform-test.dfi.local ¸
   | grep -o -E "([0-9a-f]{2}:){5}([0-9a-f]{2})"` ; do
     arp -e |grep $mac  |grep -o -P "^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}" ; done

as function:

 virt_ip () {
   for mac in `virsh domiflist $1 |grep -o -E "([0-9a-f]{2}:){5}([0-9a-f]{2})"`
   do
     arp -e |grep $mac  |grep -o -P "^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"
   done
 }