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Cluster Failover, Network Outage?

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The Question is:

The system is running on cluster with 2 AS4100 and 1 AS800 as quorom. We
 experience a system reboot on all the servers at the same time (not exactly).
 From the analysis, it showed network failure.
Is it the right scenario that all servers will reboot when they experience
 network failure? Is there any setting that permits cluster members to be
 off-line with each other for certain time before it require a reboot? Is there
 any other better setup that
can be implemented to ensure at least one member to remain alive in any network
Thanks and Regards,

The Answer is :

  The OpenVMS Wizard will assume the configuration involves two
  AlphaServer 4100 series systems and an AlphaServer 800 series
  system, but there is no cluster topology provided.
  You will need a redundant communications path if you want to
  survive a network communcations failure, obviously.
  In general, a cluster with only network communications links does
  not need and usually should not have a quorum disk (or a so-called
  quorum host).  This implies that VOTES and/or EXPECTED_VOTES are set
  incorrectly (please see the OpenVMS FAQ), or that there is a storage
  path or a secondary communications path that has not been mentioned.
  (So-called creative settings of VOTES and EXPECTED_VOTES can and do
  lead to corruptions and crashes, usually during cluster formation or
  cluster transition.)
  With a proper cluster configuration and assuming a failed network
  communications path, exactly one host should survive -- this is the
  host with the vote.  (With only network paths and no shared storage,
  there should be only one voting node.)  With redundant communications
  in a cluster configuration, multiple hosts can and should survive.
  Your OpenVMS version is in need of an upgrade to a more recent and
  preferably to a more recent and supported release.

answer written or last revised on ( 17-DEC-2003 )

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