VIOS is a critical component of any POWER virtualized environment. Best practices dictate it be kept current and backed up, but how can you back it up?
What is VIOS
We always think about the daily or weekly (user data) backup on IBMi and even to keep a good SAV21 (full system backup) but often forget to backup the VIOS, because they are running “in the background”.
The VIOS are running “under” the other LPARs (logical partitions), meaning that if they are failing, all the attached lpars are down too. It is therefore really important to backup these partitions as well. So in case anything happens, you have a backup of your VIOS and are able to put it back online quickly.
And as usual with backups, the best way is to keep them in another environment than the one you are actually using for backing up. Imagine you have a local problem like an electrical issue, an onsite hacker, a fire in the room... In that case you would lose your VIOS and the backup that would have enabled you to recover it quickly.
How can you back up VIOS
Also, note that there are multiple ways to backup for the VIOS that can be used for different type of restore. So we need to be sure to use the correct commands with the correct flags.
Some backup commands will only save the OS itself without any configuration you would have done and that are related to the server you are running on. Others will save the configuration but not the basic OS.
Make backups on external storage that are then replicated with another one on different site. This way you will always have at least 2 copies of your backups available in 2 different places.
For example, you have a Data Domain which handles NFS, it is easy to make your backup on your VIOS, copy these ones on a mounted NFS folder on the Data Domain which will then be replicated with its pair system in another location.
And for the backup types, we can backup a file that is usable to restore a “fresh” VIOS (“independent of the server we are running our VIOS on) and then restore the configuration as it was used on our server (dependent on each server this time).
Not convinced yet?