On Thu, Oct 16, 2008 at 10:02:10AM +0200, Guido G?nther wrote: > 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.
If libvirt is deployed in an environment where DLM is present & configured I've no objection to libvirt making use of it. It should just be a soft dependancy, where we also need to make a best effort for cases where DLM isn't around, even if that only works on a single host, or with a subset of storage backends. Give users the flexibility in terms of how they deploy & integrate libvirt, without imposing too many constraints. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
