ORA-01102: cannot mount database in EXCLUSIVE mode

I have encountered ORA-01102: cannot mount database in EXCLUSIVE mode error while starting new database.


SQL> startup;
ORACLE instance started.
Total System Global Area 3355443200 bytes
Fixed Size                  2929936 bytes
Variable Size            1929382640 bytes
Database Buffers         1409286144 bytes
Redo Buffers               13844480 bytes
ORA-01102: cannot mount database in EXCLUSIVE mode


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


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


ORA-01102 occurs when you are mounting(opening) database , typically because another instance is already opened in parallel (exclusive) mode.

I have noticed 2 instances are running


[oracle@rsvmsb075 ~]$ ps -ef | grep pmon
oracle    1154     1  0 Jun21 ?        00:00:06 ora_pmon_test1
oracle   15652     1  0 21:17 ?        00:00:00 ora_pmon_TEST1
oracle   15759 15626  0 21:20 pts/0    00:00:00 grep pmon
Stopped 2 instances and modified .bash_profile correctly.


Now i am able to start the database without any issues .

SQL> startup;
ORACLE instance started.

Total System Global Area 3355443200 bytes
Fixed Size                  2929936 bytes
Variable Size            1929382640 bytes
Database Buffers         1409286144 bytes
Redo Buffers               13844480 bytes
Database mounted.
Database opened.
SQL>
SQL>
SQL> select name,open_mode from v$database;

NAME      OPEN_MODE
--------- --------------------
TEST1     READ WRITE