[Linux-cluster] Adding quorum to running cluster

[Josh Gray]

I know this has been beat to death on this list but I have not found very
clear steps in the archives or even all the doc's and FAQ linked to.

Many times I've seen people say with "good" heuristics and voting settings
but have not found examples of what numbers you should use, and why.   The
two node example in the FAQ is somewhat helpful, but what about a 3+ node?

This test cluster is 3 nodes,  RHEL 5, 200gb gfs shared disk, 100mb quorum
disk

So you should start out with:
mkqdisk -c /dev/sdc -l nfsquorum
chkconfig qdiskd on

Add this to cluster.conf - is this what you should do for heuristics? What
about the votes/scores?
<quorumd interval="1" tko="10" votes="2"  label="nfsquorum">
 <heuristic program="ping 10.0.0.167 -c1 -t1" score="2" interval="2"/>
 <heuristic program="ping 10.0.0.168 -c1 -t1" score="2" interval="2"/>
 <heuristic program="ping 10.0.0.170 -c1 -t1" score="2" interval="2"/>
</quorumd>


Modify the cman statement,  but what should expected votes be?
<cman two_node="0" expected_votes="5"/>

Then reboot one node at a time?  Does qdiskd need to be started at a certain
run level, I think it's trying to start before cman on this cluster I'm
testing.

-- 
Josh Gray
Systems Administrator
NIC, Inc

Email: jgray at nicusa.com
Desk/Mobile: 913-221-1520

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