- Check similar issue related to LLAWP process under IHS vs LLAWP locked semaphores
Error: (17)File exists: unable to create scoreboard (name-based shared memory failure)
This occurs when apache has had an ungraceful shutdown (for one reason or another) and did not free up a shared memory segment. When httpd is restarted it discovers that its shared memory segment already exists, thinks an instance is already running, and terminates because it cannot allocate the resources it needs.
To fix the problem without requiring a system restart you need to find the orphan shared memory segment. To do this we need to use the ipcs command as root to list allocated segments. Typically the shared memory usage would look like the following:
<root@ /># ipcs -m -p
------ Shared Memory Creator/Last-op --------
shmid owner cpid lpid
65536 root 15572 19626
98305 root 15572 19626
<root@ /># ipcs -m
------ Shared Memory Segments --------
key shmid owner perms bytes nattch status
0x00000000 65536 root 600 524288 46 dest
0x0100e49f 98305 root 600 225304 46
You will notice 46 attached proceses (nattach) to the first shared memory segment (segment 0). These are the 46 httpd threads waiting for incoming http requests. If you see 0 attached processes, then you have a pretty good indicator of which chunk of memory to release.
You might do a ps process check to make sure the above listed pid's really are not running, Then you remove the shared memory associated with ID 0 using the ipcrm command.
<root@ /># ipcrm -m 0
You should now be able to restart apache successfully.
AIX = ipcrm -m ipcs -map|awk '$9==0 {print $2}'
