|
Storage Migration
2014/08/06 |
|
This is the example to use Storage Migration function for virtual machines.
The different point of Storage Migration from Live Migration is that
Storage Migration does not need a Storage server whivh has virtual machine images,
when executing Storage Migration, virtual machine image on a KVM host is migrated on another KVM host like follows.
Storage Migration
<------------------->
+----------------------+ +----------------------+
| [ KVM Host #1 ] |10.0.0.21 10.0.0.22| [ KVM Host #2 ] |
| +---------------------+ |
| kvm01.srv.world | | kvm02.srv.world |
+----------------------+ +----------------------+
|
| [1] |
Create a virtual machine on a KVM host.
|
| [2] | Show the file size of a virtual machine image like follows on a KVM host and move to another KVM host, create a empty disk space like follows. |
|
# show the size of Virtual machine [root@kvm01 ~]# ll /var/kvm/images total 846468 -rwxr-xr-x 1 root root 32212254720 Aug 6 22:00 centos.img ### on another KVM host ### # create a disk space which is the same size of a virtula machine [root@kvm02 ~]# fallocate -l 32212254720 /var/kvm/images/centos.img [root@kvm02 ~]# ll /var/kvm/images total 31457284 -rw-r--r-- 1 root root 32212254720 Aug 6 22:10 centos.img |
| [3] | It's OK all, execute Storage Migration like follows. |
|
[root@kvm01 ~]# virsh list Id Name State -------------------------------------- 2 centos running
[root@kvm01 ~]#
[root@kvm01 ~]# virsh migrate --live --copy-storage-all centos qemu+ssh://10.0.0.22/system root@10.0.0.22's password: virsh list Id Name State -------------------------------------- # just migrated ### on another KVM host ### [root@kvm02 ~]# virsh list Id Name State --------------------------------------- 1 centos running # back to another host, it's OK to execute normal Live Migration [root@kvm02 ~]# virsh migrate --live centos qemu+ssh://10.0.0.21/system root@10.0.0.21's password: virsh list Id Name State -------------------------------------- |