MCSG on different OS releases

[Darren Gibbs]

Our current production cluster is comprised of three nodes, 2 N-Class servers and 1 RP7400, all running HPUX 11.00. When upgrading to 11.11, can I upgrade one of the N-Class servers and still be functional as a three-node cluster for a period of time before upgrading the other two nodes?

The reason I need to do this is that the server to be upgraded first is the failover server for both of the other two nodes, but it's also used as the systst/QA environment for testing how 11.11 affects our OLTP apps and batch processes.

We're running version A.11.12 of MCSG on all three nodes.

[harry d brown jr]

Unfortunaetly I don't run MCSG, but I believe that you are correct. Basically you want to do a "rolling" upgrade.

live free or die
harry

[Rita C Workman]

What you are suggesting is called a "Rolling Upgrade", and yes you can do this. Here are some rules from my old MC/SG textbook:
Cluster config files cannot be updated until ALL nodes are at the same ver of o/s.
All MC/SG commands must be issued from the node with the latest version of MC/SG
Only 2 version of MC/SG can be implemented durring a rolling upgrade.
Binary config files may be imcompatible.
Rolling upgrade ca only be carried out on configurations tht have NOT been modified since the last time cluster was started.
MC/SG cannot be removed from a node while cluster is being upgraded.
Any new features of MC/SG cannot be utilized until all nodes are running that version of software.
Keep kernels consistent.
Hardware configurations can not be modified.

Whew !.. hope that helps !
Rita

[Dietmar Konermann]

"Mixed" clusters of 11.00 and 11.11 are fully supported... so normally you would not need to do a rolling upgrade (with its restrictions) as long as all nodes run the same SG revision.

Unfortunately you have SG 11.12 which is NOT supported on 11.11. So, after upgrading one node to 11.11 you would need SG11.13 or SG 11.14 there... and then you would need a rolling upgrade. :)

Look at the "Managing MC/ServiceGuard" manual on http://docs.hp.com/hpux/ha ... it contains a section dedicated to rolling upgrades.

Regards...
Dietmar.