[libvirt-users] migrate local storage to ceph | exchanging the storage system

[Björn Lässig]

TLDR: Why is virsh migrate --persistent --live domain
qemu+ssh://root@host/system --xml domain.ceph.xml
not persistent and what could i do about it?

Hi,
 after years of beeing pleased with local storage and migrating the
complete storage from one host to another, it was time for ceph.

After setting up a cluster and testing it, its time now for moving a lot
of VMs on that type of storage, without a disturbance if possible.

So I 'virsh dumpxml domain > domain.ceph.xml', edit the file, replace
// ---- old ---- //
<disk type='file' device='disk'>
  <driver name='qemu' type='qcow2' cache='none'/>
  <source file='domain.img'/>
  <backingStore/>
  <target dev='vda' bus='virtio'/>
  <alias name='virtio-disk0'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
function='0x0'/>
</disk>

// ---- with new ---- //
<disk type='network' device='disk'>
  <driver name='qemu' type='raw'/>
  <auth username='libvirt'>
    <secret type='ceph' uuid='53e4ba03-5ad0-4f1e-b69e-897afba272ff'/>
  </auth>
  <source protocol='rbd' name='libvirt/domain'>
    <host name='cephmon0' port='6789'/>
    <host name='cephmon1' port='6789'/>
    <host name='cephmon2' port='6789'/>
  </source>
  <backingStore/>
  <target dev='vda' bus='virtio'/>
  <boot order='1'/>
  <alias name='virtio-disk0'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
function='0x0'/>
</disk>

Now i'm calling:

root at host_a:~# virsh migrate --verbose --p2p --copy-storage-all
--persistent --change-protection --abort-on-error --undefinesource
--live domain qemu+ssh://root@host_b/system --xml domain.ceph.xml

This takes its time to copy everything into ceph, but when its over, i
never have to migrate Terabytes of Storage again.

But its not over.
The new domain definition on host_b is not persistent and after a
shutdown, local storage is used again.

What do i have todo, to make this change persistent, or is there a
better way for doing this?

(i am using libvirt 1.2.9)

Thanks in advance
Björn Lässig
-- 
Pengutronix e.K.                         |                             |
Industrial Linux Solutions               | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim        | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686         | Fax:   +49-5121-206917-5555 |