ora-27086 unable to lock file / Alertlog

ORA-27086:unable to lock file – already in use
Cause:the file is locked by another process, indicating that it is currently in use by a database instance.
Action:determine which database instance legitimately owns this file.

If you check the above Picture you will there’s two Pmon process for the same instance, So what you do is the follwing

export ORACLE_SID=swf33
sqlplus / as sysdba
Shutdown immediate;

 After shutdown database another process still up use kill -9 OS command to kill it and startup database.

Thank you
Osama Mustafa