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IP Cluster Alias and Load Balancing?

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The Question is:

I am trying to implement TCP/IP (UCX V4.1 ECO 9) cluster alias load balancing
 on a VAX cluster consisting of two VAX 4000/600's.  I am running VMS 6.2 and
 UCX V4.1.  The PC's on the LAN are running Reflections 8.0 under NT 4.0 SP6
 and making connections t
o the cluster alias via the Reflections X client.  All IP connections to the
 cluster alias go to one node on the cluster.  The DECNET connections seem to
 do the "round robin" style of load balancing OK.  I have read several of the
 articles found in the "A
sk the Wizard" repository, but none of the solutions seem to work here.  I have
 used the UCX SET NOHOST to remove the cluster alias from the host database.
 The cluster alias is being resolved by the DNS's, but all X-window clients
 connecting IP go to the
 same one node on the cluster.  This makes for a very "unbalanced" load of
 users on the cluster and supsequent performance/resource bottleneck.  The
 DNS's I have specified are all NT 4.0 based.  The PC users can specify the
 individual node name and log di
rectly onto the node.  But when the users specify the cluster alias name, the
 user is logged onto just one particular node, never the other one.  Upgrading
 the software is not an option.  One of the articles states "With the DNS-based
 alias, participating
 nodes use their own IP addresses; there is no special IP address associated
 with the cluster alias."  I'm not sure what or how to implement this
 statement. When I configured UCX on both nodes, I specified a cluster IP
 address for interface ZE0.   Are the
re any other technical write-ups on implementing TCP/IP load balancing on a
 VAX/VMS cluster ... or do you have any suggestions as to how I can solve my
 load balancing problem?

The Answer is :

  Please upgrade, to at least TCP/IP Services V4.2 with ECO, as TCP/IP
  Services V4.1 is no longer supported.
  If you are on OpenVMS VAX V6.2, you should have no application problems
  (in either user- or kernel-mode code) upgrading to OpenVMS VAX V7.2
  and TCP/IP Services V5.1, and you should seriously consider this upgrade.
  The components of interest here will be the TCP/IP Services Load Broker
  and the Metric Server -- these components do exist in the version of
  TCP/IP Services you are using, but have subsequently seen various
  enhancements in more recent versions of TCP/IP Services.

answer written or last revised on ( 12-MAR-2001 )

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