I assume there are many installations which need to go to VIOS 3.1 by October 2020 due to end of support for VIOS 2.x. Because, I did not find any upgrade procedure for “dummies”, I decided to write one which I hope people find useful. I do not cover only the upgrade process itself, but also share some advises how to do it safely and recover in case of troubles. Upgrade Virtual I/O Server to 3.1 is completely different process than before. For instance, you are going to need an extra disk to perform the operation. Interested?
Long story short – how regular VIOS update ended with few weeks investigations completed with the serious VIOS bug and the APAR (IJ25390). The latest VIO releases contain a serious bug which may affect all VIOS/SEA client LPARs on IBM Power Servers.