ORA-27100: shared memory realm already exists

I am getting the message shown below when running the cron job which restarts the database after shutdown for a cold backup:

SVRMGR> ORA-27100: shared memory realm already exists IBM AIX RISC System/6000 Error: 17: File exists

Operating system is AIX 4.3
Oracle version is 8.1.7.

When I list my shared memory segments I get:

IPC status from /dev/mem as of Mon Mar 17 09:57:11 EST 2003 T ID KEY MODE OWNER GROUP ATIME DTIME CTIME
Shared Memory:
m 0 0x5805091f --rw-rw-rw- root system 6:31:15 no-entry 6:31:15
m 1 0x47041181 --rw-r--r-- imnadm imnadm 6:32:20 6:32:20 6:32:20
m 2 0x58041181 --rw-r--r-- imnadm imnadm 6:32:20 6:32:20 6:32:20
m 3 0x4d041181 --rw-r--r-- imnadm imnadm 6:32:20 6:32:20 6:32:20
m 4 0x49041181 --rw-r--r-- imnadm imnadm 6:32:20 6:32:20 6:32:20
m 5 0x50041181 --rw-r--r-- imnadm imnadm 6:32:20 6:32:20 6:32:20
m 6 0x45041187 --rw-rw-rw- imnadm imnadm 6:32:24 6:32:25 6:32:23
m 7 0x43041187 --rw-rw-rw- imnadm imnadm 6:32:24 6:32:25 6:32:23
m 8 0x42041187 --rw-rw-rw- imnadm imnadm 6:32:24 6:32:25 6:32:23
m 9 0x41041187 --rw-rw-rw- imnadm imnadm 6:32:24 6:32:25 6:32:23
m 10 0x44041187 --rw-rw-rw- imnadm imnadm 6:32:24 6:32:25 6:32:23
m 1048587 0x843c4ab5 --rw-r----- oracle oinstall 9:48:58 9:48:58 0:30:09
m 131084 0x843c4ab6 --rw-r----- oracle oinstall 9:48:58 9:48:58 0:30:09
m 1441805 0x0003a68c --rw-r----- oracle oinstall 9:57:01 9:57:02 23:30:02
m 262158 0x843c4ab4 --rw-r----- oracle oinstall 9:48:58 9:48:58 0:30:06
m 15 0x0d052983 --rw-rw-rw- root system 9:51:17 9:51:18 8:21:18

I have one other Oracle instance running on this box. I believe this instance is using the segment with key = 0x0003a68c, based on the fact that it's cron job restarts it at 23:30 while the other data base is supposed to
restart at 0:30.

So my questions are:

1. What is causing this problem and how can I prevent it?
2. Is there any way I can tell for certain which segment is being used by which instance?
   (The other instance on the box is production and a mistake might cost me a
   few friends.)

Thanks,
Peter Schauss
Northrop Grumman Corporation

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
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Author: Schauss, Peter
  INET: pschauss_at_northropgrumman.com

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