Forum OpenACS Q&A: Re: Fatal: received fatal signal 11 - new error after years!
Just a small note: In order to have the nsd process generate a core dump just be sure to increase the maximun size of core files the user running the nsd process can create ( usually you want to have an unlimited size, just run 'ulimit -c unlimited' before you start the nsd process, you can add that temporarily to your start up script or so).
Then the core dump will be written to the Aolserver home directory ( e.g. /usr/local/aolserver/ ). Also you have to be sure that the user running the process has the correct permissions to write into that directory otherwise it wont be able to generate the core dump.
Also, in case you have nasty code that changes directories for whatever reason, it can happen that the core dump will be written to a different directory other than the Aolserver home directory, so just be aware of that.