two pmon running for same db(No parallel)

In one Production Box many(7) Databases running....and when I run ps -ef|grep pmon, 2 pmon entries found for the same database.....

oracle 12656 1 0 May 25 ? 12:26 ora_pmon_usarpt
oracle 8481 1 0 Jul 2 ? 0:30 ora_pmon_usarpt

checked alert log and found someone(I am new to this envirnment) tried to open already running database by mentioning different pfile option...so I guess 2nd instance is running too.....

Can anyone tell me what is the best/safest method to shut down the second instance without affecting the production DB....my fear is I should not shut down the production thing....

Not much found in metalink/google etc on this.....

Surprised......I have seen in this forum so many difficult questions were answered by big guns easily.....why not for this one?

Common friends!(adewri, jovery, marist89, padmam, pando, sambavan, SANJAY_G,slimdave, DaPi,Abhaysk ...sorry if I missed out any senior guys here!) help me out this newbie.....

How about shutdown immediate? Shutdown the database that's supposed to be down and then kill -9 the rest. You waited 8 days for that?

First make sure you that your assumptions are correct.

Look at the job started time. For an instance the time stamp will be same for all the background processes.

Example

ps -ef |grep TEST

oracle 25978 1 0 05:29:45 - 0:00 ora_pmon_TEST
oracle 47028 1 0 05:29:45 - 0:00 ora_ckpt_TEST
oracle 54108 1 0 05:29:45 - 0:00 ora_arc0_TEST
oracle 56868 1 0 05:29:45 - 0:00 ora_dbw0_TEST
oracle 66650 1 0 05:29:45 - 0:00 ora_lgwr_TEST
oracle 67222 1 0 05:29:45 - 0:00 ora_reco_TEST
oracle 72320 1 0 05:29:45 - 0:00 ora_smon_TEST

So check the PMON background process (take care of the server process ) and kill it which is having a different time stamp. And use ipcs command to release the semaphores and memory if allocated.

Note: I never encountered this problem... So never tested....

Best of luck!

Regards,
Thomas

Dear Ramg

Strange situation !!!!

pl let me know the result after you shutdown immediate

$ ps -ef | grep pmon

I want to know your result eagerly.

Thanks