3-node sun cluster, does it require quorum disk/devices?

hi,

so is it an official SUN guideline that for 3node cluster we DO NOT require any quorum devices? is it a mandatory when we install sun clustering 3.1 that we hv to specify a quorum disk?

Reason being my vendor is commissioning my 3node cluster and specifying ONE quorum disk!! that will be 4votes for my 3node cluster! i find it ridiculous and shocked! but i need to have a firm feedback b4 i light my concern to them...

any guru can comment further? many thanks in advance.

nickyng at 2007-7-6 23:15:48 >

There are 2 ways to solve the quorum problem for a 3 node cluster.

1. you do not define a QD. You then have 3 votes and you'll need 2 of them to form the cluster. Disadvantage. If 2 nodes fail, your cluster will not work any more.

2. you define a QD attached to all 3 nodes. Now you have 5 votes (3 from the nodes and 2 from the QD), and will need 3 to form the cluster. I.e. one(1) node plus the QD are sufficient to form a cluster.

Now, you can decide, depending on your needs, what you want.

And as you could see, a QD is not required for clusters with more than 2 nodes.

A 2-node cluster without a QD would be pretty useless, as any outage of one node would make your whole cluster fail.

Regards

H.

HartmutS at 2007-7-6 23:15:48 >