Version
All versions
Explanation
Unable to connect as SYSDBA.
Cause
This error occurs if a client tries to connect to the database as SYSDBA when there already is another client connected as SYSDBA.
Action
Only one client can be connected as SYSDBA per session.
1. Check whether a previously connected session exists.
2. If necessary, clean up the session.
3. Reconnect.
Reference
N/A