ORA-46952 password is just OK, then why?

 This is expected in an oracle dataguard environment (version 19c mainly, but any version > 12.2 expected to face this issue)

Have you wondered if you will ever had to start the MRP using "ALTER DATABASE " command from sqlplus after having broker configured?

When you downgrade the password file format from 12.2 to 12 and then try putting it back to 12.2, you will hit ORA-46952 "format mismatch for the password file on a standby database"

On this circumstance, the broker based recovery will kick off MRP and MRP will fail in next few mins.

The workaround as per oracle KEDB is to

1. Remove the password file from standby

2. Initiate recovery using "ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;"

3. Copy the password file from primary to standby

4. Now MRP should be stable

5. Send couple of archives over and verify

6. Now stop/start MRP from broker, you should be all set.

Note any other tries you make, like recreating the password file format 12 or 12.2 again. Copy old or create new password file, none of them will work.

The above method only will work, no idea what the cause is yet.

Yes there is a 12.2 password format new feature which sync password changes in primary with standby using redo log now (which can also be controlled through a log ship setting)

Phew! as my son says what a day :)