On Thu, 5 Apr 2012, James Harper <james.harper@bendigoit.com.au> wrote:
3 nodes is the practical minimum for any sort of distributed system no matter how you do it. With less than 3 you can't have quorum if one node goes away.
You can have a dedicated quorum/witness server (or device) that doesn't provide any other cluster resources. There are often better ways of achieving similar results than a 2 node cluster though.
Calling the "dedicated quorum server" something less than a "node" doesn't mean much unless you pay MS style license fees for each node. If you are doing something like renting servers from a company like Hetzner.de then each server has the same amount of storage so it wouldn't be practical to have a server manage the quorum but not have storage. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/