Applying OS updates with RDQM

RDQM uses a DRBD kernel module which must be compatible with the current OS kernel level.

If OS updates are made which update the OS kernel level then a new DRBD kernel module might be required. See https://ibm.biz/mqrdqmkernelmods for guidance on compatibility between DRBD kernels and OS kernels.

Typically, a DRBD kernel update is required when the OS kernel branch is updated. For example, from RHEL 7.7 (3.10.0_1062) to RHEL 7.8 (3.10.0_1127).

In this case, follow the procedure Update DRBD kernel module before nodes are rebooted into a new kernel.

If you have already rebooted nodes into a new kernel, and find that RDQM does not run, follow the procedure Update DRBD kernel module after a node has rebooted into a new kernel.

The rdqmstatus command gives information about the OS kernel level and DRBD kernel module level, see Viewing RDQM and HA group status, Viewing DR RDQM status, and Viewing DR/HA RDQM and HA group status.