Relying in Guaranteed Restore Points? Be careful!

Hi all,

Are you relying on Guaranteed Restore Points (GRP) as a fallback plan for your migration or upgrade strategy? Be careful!

When performing some non-Prod upgrade with the Autoupgrade tool,  after completing the upgrade, I wanted to roll it back and go through the process again,  This is what happened:

SQL> startup
ORA-29702: error occurred in Cluster Group Service operation

When looking for it found this blog post from Mike I missed the last year:

This means my database is not starting anymore! Oh man, glad that I’m in the testing phase!

This caused by of Bug 31561819 – Incompatible maxmembers at CRSD Level Causing Database Instance Not Able to Start.

As per Mike’s post, “you don’t need to even restore or flashback a database to hit this error. A simple instance in NOMOUNT state leads to the same error. Without even any datafile.”

The bug is fixed on:

  • (Oct 2020) OCW RU
  • (Oct 2020) OCW RU
  • (Oct 2020) OCW RU

As being, you should include this patch BEFORE starting any move! Do it right away if you are on these versions!

Also, be aware of the latest change regarding Restore Points propagation on 19c, as per MOS Automatic Propagate Restore Points from Primary to Standby site in 19C (Doc ID 2463082.1)

In my case, the usage is exactly for a 12.1->19c upgrade. So, the fix is not even available (no Extended Support in place). As being, we had to think on alternate fallback plans, like a physical standby. But this is a topic for another post.

So for YOU:

  • Apply this patch if you can!
  • If not, be very careful on the fallback plans and as usual: Test, Test and Test!

See you next post!