Home
Trouble shooting
 

Cry about...
Oracle Troubleshooting


ORA-01102: cannot mount database in exclusive mode


Symptom:

When opening or mounting the database, the following error is generated:

ORA-01102: cannot mount database in EXCLUSIVE mode.

Cause:

I have only come across this error when using Oracle Parallel Server (OPS). Here, this error indicates that another instance has already been mounted in exclusive or parallel mode.

Possibly Remedies:

  • Mount the database in parallel mode.

  • Shutdown all other instances before mounting the database in exclusive mode.

  • Try stopping and then restarting the service 'OracleService<SID>'.