We ran into an interesting situation recently when MRP failed on a standby with the error:
ORA-38882: Cannot drop tablespace UNDOTBS2 on standby database due to guaranteed restore points.
The background was that we had to remove a node from our primary RAC to upgrade the server. We did not remove any nodes from the standby. After the node was removed from the primary, MRP failed on the standby with the above error. As far as we could remember or check, we did not have a guaranteed restore point on the database. A google search led us to Mike Dietrich’s Blog, where he had responded to a similar error in a different context. The link is
Mike Dietrich’s Blog About Oracle Database
We were not using a PDB, but since we did not have any other ideas, we decided to try Mike Dietrich’s solution and issued the following alter:
alter system set "_allow_drop_ts_with_grp"=true;
After the above alter, the database was bounced, and MRP started successfully.