./cogconfig.sh - intermittant starting problem

SUSE 11 SP1 - Cognos 8.4.1 - Content store is Oracle 11.2
cogconfig.sh works to start and stop Cognos.
If I make changes to the configuration, sometimes the start hangs and doesn’t start.
If I exit cogconfig.sh, I don’t have any cognos operating system processes running.
If I reenter cogconfig.sh and try to start it fails.

If I reboot the SUSE server, then cogconfig.sh starts fine. Why?
Is there a lock file, hung port or something that I can clear to resolve the issue?
I don’t want to have to reboot the SUSE server to restart Cognos.

Any insight into this would be appreciated.

When it fails do you have a cogserver.log file? if so what does it say?
if not, the tomcat(?) application server (java.exe) is not started. you should start troubleshoot there.

what Cognos processes are running when the startup fails?

another option can be the memory you assign in Cognos configuration manager JVM setting. If the memory set there is more than Cognos can allocate Cognos will not start. What value do you use?