ORA-01102 cannot mount database in exclusive

The Oracle docs note this on the ora-01102 error:

ORA-01102 cannot mount database in EXCLUSIVE mode
 

Cause: Some other instance has the database mounted exclusive or shared.

Action: Shut down the other instance or mount in a compatible mode.

 

 

 

 

 

POSSIBLE SOLUTION:

 

      Verify that the database was shutdown cleanly by doing the following:

1. Verify that there is not a "sgadef<sid>.dbf" file in the directory
"ORACLE_HOME/dbs".

% ls $ORACLE_HOME/dbs/sgadef<sid>.dbf

If this file does exist, remove it.

% rm $ORACLE_HOME/dbs/sgadef<sid>.dbf

2. Verify that there are no background processes owned by "oracle"

% ps -ef | grep ora_ | grep $ORACLE_SID

If background processes exist, remove them by using the Unix
command "kill". For example:

% kill -9 <Process_ID_Number>

3. Verify that no shared memory segments and semaphores that are owned
by "oracle" still exist

% ipcs -b

If there are shared memory segments and semaphores owned by "oracle",
remove the shared memory segments

% ipcrm -m <Shared_Memory_ID_Number>

and remove the semaphores

% ipcrm -s <Semaphore_ID_Number>

NOTE: The example shown above assumes that you only have one
database on this machine. If you have more than one
database, you will need to shutdown all other databases
before proceeding with Step 4.

4. Verify that the "$ORACLE_HOME/dbs/lk<sid>" file does not exist

5. Startup the instance