Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Tue, Apr 17, 2012 at 3:05 AM, Arnold Krille <arnold at arnoldarts.de> wrote: > Hi, > > > On 15.04.2012 22:05, Björn Enroth wrote: >> >> I am looking for information of how to deal with a KVM three node cluster >> with DRBD >> I have a "baby machine" ubuntu 11.10 pacemaker/drbd cluster with two >> nodes, >> local disks with drbd setup in between. This is working flawless. >> >> My challenge now is that I want to add a third node with the same setup. >> How do I handle drbd in this setup? I'd like to have all nodes active, to >> be able to migrate resources, mainly kvm virtual guests, around the >> cluster >> as I see fit. I'd also like pacemaker to be able to dynamically handle the >> load. > > > While drbd is great, this is exactly our intended use-case and also exactly > the reason I am looking at other storage solutions. drbd can't do more than > two nodes. > > You can of course distribute the drbd-resources so that some are n1/n2, some > n2/n3 and some n1/n3, but that becomes an administrators nightmare. And once > you decide that you need four nodes with the data present on at least three > nodes, you are stuck. > You can layer the drbd-resources but that is more meant for semi-distant > mirrors and manual fail-over. > And if you want live-migrations for your vms with more then two primary > filesystem nodes... > > I am currently looking at glusterfs, there is also moosefs and ceph(fs), but > only the first is meant to be stable enough that redhat gives commercial > support for it. There are also other distributed cluster filesystems like > lustre, but they lack redundancy. FWIW, I agree that GlusterFS is probably the best available option at this time, for this use case. I'd recommend Ceph (Qemu-RBD, specifically) if the virtualization cluster was larger, but the GlusterFS option combines excellent ease-of-use with good redundancy and would probably be your best bet for this cluster size. Cheers, Florian -- Need help with High Availability? http://www.hastexo.com/now