Re: Partitioned cluster question (reboot during lost quorum)

hoffman@xxxxxxxxxxxxxxxxxxxx wrote:
If you would like to learn how to properly set the VOTES and the
EXPECTED_VOTES parameters, do please consider reviewing the text on
these settings in the OpenVMS FAQ.


It will reboot, but will hang awaiting quorum.

MC SYSGEN HELP SYS EXPECTED_VOTES mentions the MAXIMUM number of
expected votes, not the minimum one.

So after a power failure, if you power up your nodes one by one, you
mean to say that each node would just get get stuck near the "waiting to
form or join cluster" until it finds enough votes lying around the
ethernet to get to a quorum based on the maximum expected votes ?

(I haven't had enough experience watching this happen to really know for sure).

I was under the impression that when node boots and is all alone (eg:
forms a new cluster), it proceeds with a quorum of its own votes/2 + 1,
and then the quorum is dynamically adjusted updwards as other nodes join
the cluster.


So EXPECTED_VOTES / 2 + 1 defines the MINIMUM number of votes necessary
for any node to proceed with booting beyond the awaiting to form/join
cluster ?

Perhaps the documentation should say it this way instead of talking
about MAXIMUM number of votes to be expected.

I once tried to ajuset expected_votes downwards with DCL (SET
CLUSTER/EXPECTED_VOTES and that didn't work. Does this mean that SET
CLUSTER/EXPECTED_VOTES will not let you being the number below the
SYSGEN parameter EXPECTED_VOTES ? but If that number does grow beyond
it, you can then use the DCL command to bring it back down t the SYSGEN
value ?

(I tried to use this while in the process of reconfiguring the cluster
when I knew that leaving NODE X up and running would not jeoperdize
integrity but it didn'T have anough votes to keep on working so I ended
up without service with the other node rebooted).


<http://www.hp.com/go/openvms/doc/>

Sorry, I am only familiar with http://www.hp.com/go/vms/doc/ :-)
.

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