[libvirt] (no subject)
On Wed, Oct 15, 2008 at 09:59:12PM +0100, Daniel P. Berrange wrote:
When you get to that level of cleverness, it seems to me that it is
verging
on a complete re-implementation of DLM (distributed lock manager), which
really, AFAIK, needs a proper cluster setup so it can safely fence
mis-behaving nodes, and avoid quorum/split-brain problems.
I've been toying
with the idea of using DLM for libvirt earlier this
year [1](but infered from other postings on the list that this would be out
of scope for libvirt - probably should have asked). I looked at vm based
locks then but having storage based locks is even better.
Currently you have to make sure "manually" that people using i.e.
virt-manager[2] don't accidentally fire up VMs managed via e.g.
rgmanager.
Having cluster wide storage based locks would be an awesome solution.
-- Guido
[1] using the rather simple lock_resource() and unlock_resource() API:
http://git.fedorahosted.org/git/cluster.git?p=cluster.git;a=blob;f=dlm/do...
[2] i.e. by having virt-manager hooked to all libvirtds in the cluster
and allowing to start each uuid only once