How to migrate KVM based VMs running in LVM setup to Vmdk images

kvm-virtualizationmigrationqemu

I am using KVM on Ubuntu Server 10.04. and Virtual Machines are running on it in LVM.
I have to migrate some of them to Vmware server.How can I achieve this?
I searched and came across some links but they all talked converting vmdk images to qcow or so.In this case I have OS in LVM.

I also looked at man page of qemu-img and as I understand it should do what I am asking in this thread. But how exactly should I proceed in this case.Since it is not a file based image (OS running in an LVM which has filesystem in that LVM).
So I am not able to understand what should I be doing to achieve the same.
Can I achieve the above with snapshots of LVMs rather than shutting down the VM itself.

Best Answer

Yes, you can create an LVM snapshot volume and convert it with qemu-img:

lvcreate -L592M -s -n myvolume /dev/myvg/myvolume_snapshot
qemu-img convert /dev/myvg/myvolume_snapshot -O vmdk myvolume.vmdk

Related Solutions

Linux – mount qcow2 snapshots

You should apply the snapshot and mount the image like always. It's better to create a snapshot right before applying if you want to turn back to the original disk contents before you do these operations. After you apply the snapshot you just mount the image with qemu-nbd as always:

# modprobe nbd max_part=8
$ qemu-img snapshot -c backup image.qcow2
$ qemu-img snapshot -a old_snapshot image.qcow2
$ qemu-nbd --connect=/dev/nbd0 image.qcow2
# mount /dev/nbd0p1 /mnt

You might want to save snapshot separately and mount it as another disk drive. For this you should use convert comand for qemu-img.

$ qemu-img convert -s old_snapshot image.qcow2 old_snapshot.qcow2
$ qemu-nbd --connect=/dev/nbd0 old_snapshot.qcow2
# mount /dev/nbd0p1 /mnt

See man qemu-img(1) and qemu-nbd(1) for more details.

Lvm – Snapshot a KVM guest with non-file storage

If you are going down the libvirt path why aren't you using the libvirt snapshot facility?

If you read the site you will see that it says:

Disk snapshots exist in two forms: internal (file formats such as qcow2 track both the snapshot and changes since the snapshot in a single file) and external (the snapshot is one file, and the changes since the snapshot are in another file).

Also

disk
This sub-element describes the snapshot properties of a specific disk. The attribute name is mandatory, and must match either the <target dev='name'/> ...

If your VM's disk is an LV you specify it using ...dev='lv_name'...

Best Answer

Related Solutions

Linux – mount qcow2 snapshots

Lvm – Snapshot a KVM guest with non-file storage

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