Hello Tommi,
According to the documentation, there are two possibilities.
I have tried backup/restore.
Unfortunately it did not work with an upgrade or reinstallation to RHEL 9.0. Case is open for it.
I would do PowerVC backup.
RHEL update from 8.4 to 8.6.
Installation of PowerVC 2.1.
Restore from backup.
Greetings
Andre
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Andre Lutz
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