On 27/02/13 20:19, Nikolaos Milas wrote:
Any suggestions?
I am looking for a solution that would work in creating a failover cluster with two nodes, utilizing (two) CentOS 6 VMs, each on a different data center; this requirement makes technologies like drbd unusable (due to the inherent lack of complete link reliability between the two nodes).
Not sure how one can provide full HA between two datacenters with a single unreliable link in any case. You should arrange multiple physically independent links before you even think about doing failover the "good" copy is.
- otherwise you stand to find yourself in a sticky situation when something odd happens. DRBD "split-brain" also applies to other solutions such as clustered and replicating filesystems. It hurts like hell when your storage gets damaged and you have no way of telling what
*If* you can wire in a second circuit between the two DCs (and preferably a 3rd you will be OK for any HA scenario. Ie, one circuit for data+DRBD traffic (ideally this should be 2 circuits) and another for heartbeat/fencing etc.
That said, I've heard good things about GlusterFS but I'm still not sure I'd trust it for corporate-level offsite HA.
This kind of thing is cheap to do badly and expensive to do right.
Cheers
Alex