My glassfish process kept dying with "Too many open files" in the log.
I'm not surprised that it has too many - it has quite a few large applications running - but how to increase this?
ulimit -n shows that the user has a default of 1024.
But ulimit -n 2048 gives -su: ulimit: open files: cannot modify limit: Operation not permitted
Some digging leads to /etc/security/limits.conf
Here we added: