Here’s some information that I had picked up on Live Partition Mobility for IBM i during the COMMON conference in May 2012. IBM readers, please feel free to comment and suggest changes if I have anything wrong.
Here’s what I learned about Live Partition Mobility (LPM), the ability to move a running IBM i partition from one IBM Power machine to another. In addition to this information, Dawn May, Senior Technical Staff Member at IBM Rochester, wrote a very detailed piece about IBM requirements for using Live Partition Mobility, which can be accessed by clicking here.
- Live Partition Mobility will be controlled through the HMC. Good thing they decided to keep it😉
- The two partitions (the source and the target) must have equal capabilities in terms of hardware or the transfer may fail
- If running 5250 sessions, the two partitions must have equal capabilities in terms of interactive capability, or the transfer may fail if there are interactive sessions running
- The larger the pipe, the quicker the transfer between the boxes
- There is a little bit of a grey area when the partition will exist on both boxes but it is fairly short
- Both boxes must have virtualized storage
- LPM occurs when the memory and CPU are transferred between the boxes and the receiving box is pointed towards the storage of the sending box
- LPM transfers can occur for a) running partitions; b) suspended partitions; and c) inactive partitions. It is not limited to active partitions
- IBM has not announced how it will handle transferring license keys between the two boxes. It’s unclear what state the licensed program licenses will be in when they reach the new box. There may be a good chance that when the licenses move to the new box, they will treated the same way as when you transfer licenses from a production machine to a Capacity BackUp system (CBU). ie, the licenses could revert to 70-day temporary licenses.
- It’s also unclear how LPM will handle license keys from third-party vendors. Third-party licenses are frequently keyed to the serial number of the box, the partition ID, and some other machine-specific parameters. You could be able to transfer a live partition only to find you still have to run certain procedures before the third-party software will work on the new partition, because the software won’t run on a new box with a different serial number, LPAR ID, etc.
- IBM isn’t planning on its users using LPM for HA or DR. It has uses for maintenance, load balancing, upgrading firmware, upgrading hardware, and other tasks but it’s not a great fit for HA/DR. For one thing, it’s dependent on shared disk between the two machines. If a disaster wipes out the disk from the source machine, there will be no recovery.
- You probably won’t be able to transfer partitions from a lower level P-Group box (say a P05) to a higher-group box (P10 or above). This is due to licensing. You can’t run cheaper licensed programs on a more expensive box.
That’s it for now. Please feel free to chime in with any other info IBM or non-IBM people may have found on LPM.