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Recovering from a domain in a strange state

Strange? How so?

On the old hypervisor, the domain is shut off but persistent

[root@kvm01b ~]# virsh list
 Id Name                 State
----------------------------------

[root@kvm01b ~]# virsh list --all
 Id Name                 State
----------------------------------
  - mailserver1          shut off

[root@kvm01b ~]# virsh dominfo mailserver1Id:             -
Name:           mailserver1
UUID:           b4d4b8db-13e5-4269-a40c-5c5311d8e28e
OS Type:        hvm
State:          shut off
CPU(s):         1
Max memory:     4194304 kB
Used memory:    4194304 kB
Persistent:     yes
Autostart:      disable
Managed save:   no

[root@kvm01b ~]#

On the new hypervisor, the domain is running but not persistent

[root@kvm02b ~]# virsh list --all
 Id Name                 State
----------------------------------
  1 webserver1           running
  9 dbserver1            running
 11 mailserver1          running

[root@kvm02b ~]# virsh dominfo mailserver1
Id:             11
Name:           mailserver1
UUID:           b4d4b8db-13e5-4269-a40c-5c5311d8e28e
OS Type:        hvm
State:          running
CPU(s):         1
CPU time:       1136.4s
Max memory:     4194304 kB
Used memory:    4194304 kB
Persistent:     no
Autostart:      disable
Managed save:   no

[root@kvm02b ~]#

So?

We want the running domain to be persistent

How did it get this way?

I had run this command

[root@kvm01b ~]# virsh migrate --live --verbose mailserver1 qemu+ssh://kvm02b/system

I should have used included --persistent --undefinesource as options to move the domain configuration information over to the target host.

How make a running VM persistent

Dump the XML and run `virsh define` on it

[root@kvm02b ~]# virsh dominfo mailserver1
Id:             11
Name:           mailserver1
UUID:           b4d4b8db-13e5-4269-a40c-5c5311d8e28e
OS Type:        hvm
State:          running
CPU(s):         1
CPU time:       1141.6s
Max memory:     4194304 kB
Used memory:    4194304 kB
Persistent:     no
Autostart:      disable
Managed save:   no

[root@kvm02b ~]# virsh dumpxml mailserver1 > /tmp/spinal-prd.xml
[root@kvm02b ~]# virsh define /tmp/spinal-prd.xml
Domain mailserver1 defined from /tmp/spinal-prd.xml

[root@kvm02b ~]# virsh dominfo mailserver1
Id:             11
Name:           mailserver1
UUID:           b4d4b8db-13e5-4269-a40c-5c5311d8e28e
OS Type:        hvm
State:          running
CPU(s):         1
CPU time:       1142.6s
Max memory:     4194304 kB
Used memory:    4194304 kB
Persistent:     yes
Autostart:      disable
Managed save:   no

[root@kvm02b ~]#

How to get rid of the old XML config info on the old hypervisor

Run `virsh undefine` on the domain id

[root@kvm01b ~]# virsh list --all
 Id Name                 State
----------------------------------
  - mailserver1          shut off

[root@kvm01b ~]# virsh undefine mailserver1
Domain mailserver1 has been undefined

[root@kvm01b ~]# 
[root@kvm01b ~]# virsh list --all
 Id Name                 State
----------------------------------

[root@kvm01b ~]#