You're running Symantec Mail Security for Domino 8.x and are experiencing random Domino terminations (without NSD) with the console message: "PANIC: Unexpected OS error returned to logger:"
This occurs especially when the server is under heavy load.
Console log shows:
[262154:00002-00001] PANIC_SQLO _rc = 0x00000000
[262154:00002-00001] PANIC_SQLO _hiCode = 0x0000012E
[262154:00002-00001] PANIC_SQLO errno? = 0x00000000
[262154:00002-00001] PANIC_SQLO file = logger/amqhsofn.c
[262154:00002-00001] Unexpected OS error returned to logger:
Stack base=0x2FF20C00, Stack size = 1008 bytes
PANIC: Unexpected OS error returned to logger:
Stack base = 0x2ff20c00, Stack size = 4784 bytes
Fatal Error signal = 0x0000000b PID/TID/DBX-TID/K-TID = 262154/1/1/1499207
A possible cause for this error may be related to disk space missing on Domino data partition/folder.
This is not a problem of Symantec Mail Security for Domino.
To solve this problem, make sure there's enough disk free space on the Domino data partition (generally at least 5-10 GB)