Migrating cluster to new nodes

[Stuart Powell]

I have in place a two node SG cluster running HP-UX 11.00 and SG 11.09. I am planning on replacing the nodes with two newer servers running HP-UX 11i and the latest version of SG. I'll be connecting the new servers to the same SAN, and therefore will have the hosts assigned to the same LUN's. I'm looking for confirmation that to accomplish the transition I need to follow these steps:
1. Create the special files for all of the LUN's on the arrays.
2. Copy the vg maps from the existing cluster to the new cluster and build the vg's.
3. Copy the cntl files from the existing cluster to the new cluster.
4. Edit the cluster ASCII file for the new nodes.
5. Run cmapplyconf on the new cluster.
6. Halt the existing cluster.
7. Start the new cluster.

Stuart Powell

[Karthik S S]

It is perfect from the OS point of view. But also you need to take care of the applications that are configured under the packages.

And there are some changes to the package control/script files of SG 11.15 as compared to SG11.09.

-Karthik S S

[Kent Ostby · Accepted solution]

Stuart --

A few things to keep in mind.

1) Networking configuration will probably change significantly. This was probably part of what you had in mind in #4, but its worth noting seperately.

2) I'm not sure you'll be able to do #5 before #6. If these boxes are on the same subnet, I dont think SG will allow you to cmapplyconf with the cluster up on the same subnet.

3) Make sure you are installing the proper SG patches to match the new machine/OS.

Best regards,

Kent M. Ostby

[G. Vrijhoeven]

Suart,

Not sure. When the cluster is active on old nodes i am not sure it is possible to do a cmapplyconf on the new one. ( cluster lock disks ) if this fails you need to bring the old cluster down before the cmappyconf.

5 a cmapplyconf on all package file
so you have packages to start.

The halting of the cluster will do a vgchange -c n on all vg's specified in the cmclconfig.ascii file. It can happen that you have mode vg's so do a manual vgchange -c n on all if any remaining vg's


HTH,

Gideon

[Stuart Powell]

Kent & Gideon;

Good point on the order of step 5 and 6. I was planning on including the subnet information on step 4.

Stuart