Just reproducing from Metalink....see this helps u....

RDBMS Version: 8.1.7.4
Operating System and Version: Windows 2000 service pack 2
Error Number (if applicable): osd-04400
Product (i.e. SQL*Loader, Import, etc.):
Product Version:

Instance can not mount ,

Hi ,
We have three instances running in the same machine. We are not able to startup ony instance. The alert file for all the three instances contains following errors.

" ORA-09341: scumnt: unable to mount database
OSD-04400: unable to acquire internal semaphore for process
O/S-Error: (OS 183) Cannot create a file when that file already exists. "

All the three instances are very new and nobody connected to any databases.

What is the main problem here.

Some background on set up:
The Win 2k server has 1.3 GB RAM, Does this RAM not sufficient to use three instances ? Each of the instance SGA is as given below

instance 1 --->97MB
instance 2 ---> 112 MB.
instance 3 ---> 97 MB.

Appreciate your help on this .

Regards

Srini





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From: Oracle, Kathy Ting 14-Nov-02 06:32
Subject: Re : Instance can not mount ,



The errors are generated because the same DBName for the databases are being used in the INITsid.ORA file. It is NOT possible to have two databases up with the same DBName on an NT Box (even with different ORACLE_SIDs).

The name of the semaphore, scumntsem_, is created on mounting the database.

When starting another instance, even with a different ORACLE_SID, the same DBName will cause a conflict with the existing semaphore.

This was done to avoid misusages when creating other databases
on the same box.


Stop all instances. Modify the services to MANUALLY start. Modify the INITsid.ORA file. Reboot the server. Start each instance.





Thank you for using the MetaLink Forum,
Kathy
Oracle Support.



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From: srinivasulu kvs 14-Nov-02 07:36
Subject: Re : Instance can not mount ,


Hi Kathy,

The fact here is three instances already have three different "db_name" in their init.ora file. I checked with V$parameter also.

What could be other reasons ??

Regards

Srini






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From: Christian Adams 18-Nov-02 15:01
Subject: Re : Instance can not mount ,


Srini,

You are not alone! I had the same thing happen yesterday to one of four databases (8.1.7.3.0) on a server running Windows 2000 Service Pack 2. And like you, these databases have different DB_NAMEs. Stopping and restarting the Oracle service for the instance in question did not fix it for me, so I had to reboot the server.