how to diagnose if the oracle goes down

[castlerock]

Hi,
All of sudden my oracle database went down...while connecting to it i got the follwing error " shared memory realm exist" I have checked the bdump folder files like
ORCLALRT
orclSMON.TRC

the alert file has the startup time, the orclsmon trace file didnt show any latest error.


How to find the reason behind this..?

Oracle Environment:
NT,ORACLE 9i

Thanks,

[Dilippatel]

You can check Alert log file, or any other trc file written at BACKGROUND_DUMP_DEST.

You can do shutdown abort and restart the database.

Also you can check os utility, if any error log there (in event viewer in case of NT ).

[akhadar]

Originally posted by castlerock
Hi,
All of sudden my oracle database went down...while connecting to it i got the follwing error " shared memory realm exist"
Thanks,

ITs common error.Usually u will get this error when u are trying to connect to DB when it is down.As said by Dilip if u didn't find any error messages on ALERT.LOG then it could be OS which forces the DB down.