[ClusterLabs] DRBD, dual-primary, Live-Migration - Cluster FS necessary ?

[Eric Ren]

Hi,

On 09/07/2017 01:30 AM, Lentes, Bernd wrote:
> Hi,
>
> i just want to be sure. I created a DRBD partition in a dual primary setup. I have a VirtualDomain (KVM) resource which resides in the naked DRBD (without FS), and i can live migrate.
> Are there situations where in this setup a cluster fs is necessary/recommended ? I'd like to avoid it, it causes more complexity.
With cluster FS (ocfs2, gfs2), you can use qcow2 files as images for the 
VM, then you have the features that qcow2 file provides, like
your image can grow as data is added, instead of allocating the whole 
image space at creation.

Eric