IBM Power Virtual Server tip: Multiple LPARs with the same Serial Number

One thing we miss when moving our IBM Power workloads to the cloud, specially IBM i LPARs, is the serial number management with our on-premise boxes.

We can have a production box and a development system, so we can group LPARs based on SLAs and serial numbers.

Serial numbers can make a difference with some software products. Some vendors charges you per serial number, and cloud environments love to distribute your VMs/LPARs in different boxes, to load balance their usage.

IBM Power Virtual Server has some tricks... great ones

• When working with IBM Power Virtual Server you can use VM pinning to avoid changing your serial number when IBM needs to performance maintenance. This makes your serial number persistent.
• The second trick is the Server Placement Group feature: We can create one or more placement groups to force our new LPARs to be placed in the same box.

• ...We can also use placement groups to AVOID using the same server. This is useful for High Availability environments.

Now... Diego's magic trick

The server placement group feature is great, but sometimes we get stuck with the amount of resources in one box, and we cannot select the box we want.

But we can use this trick:

• You have your actual Server Placement Group, and you are not able to create a new one.
• You can create a second Server Placement Group. Just keep the previous one on.
• Export your LPAR to an Image Catalog (disk)
• Create a new server instance (LPAR) on the second Server Placement Group, and use your exported LPAR as your install media.
• Add all the servers you need in this serial number
• Remove the old LPAR(s) from the first Placement Group
• You are done, now you have your LPARs running in a different box.

Remember there is a limit for total amount of CPUs, based on the system model. Use this trick with responsibility.

Ask your IBM or IBM Business Partner consultant for advice and a free PoC, and test how you can save money with IBM Power Virtual Server.

Good Luck!

Diego E. KESSELMAN