ORA-16753 error troubleshooting
1. Use dgmgrl to set the database to read-only mode:
DGMGRL> edit database dg_name set state = read-only;
ORA-16753 Resource guard cocould not open standby database
Cause: Resource guard cocould not open standby database.
Action: Check the Data Guard console log for further details.
2. view the dg log $ {bdump}/drc $ SID. log record.
We can see a key piece of information:
ORA-16006: audit_trail destination incompatible with database open mode
Originally, we can see audit_trail = db through show parameter audit_trail.
3. audit_trail parameter description
AUDIT_TRAIL = {none | OS | db, extended | xml, extended}
Db: Directs audit records to the database audit trail (the SYS. AUD $ table), before t for records that are always written to the operating systemaudit trail. use this setting for a general database for manageability.
If the database was started in read-onlymode with AUDIT_TRAIL set to db, then Oracle Database internally sets AUDIT_TRAILto OS. Check the alert log for details.
For more information, see http://docs.oracle.com/cd/B19306_01/server.102/b14237/initparams016.htm.
4. Set audit_trail to none and restart the database.
Alter system set audit_trail = none scope = spfile;
Solve the problem after restart.