We have trouble with Tomcat 5.5 which stops at night on our production servers (Linux CentOS 4.8) and we have no idea why it stops... There is no Tomcat\'s log in catalina.out o
1) Make sure you know where stderr is redirected and check if anything got printed there.
2) Check the memory limits on Tomcat and how much free memory does the system have. Review the Linux system logs under /var/log to see if anything suspicious happened during the time. For example, kernel can randomly kill a process (almost) without a trace if the system is running low on memory.
We've ran 5.5 in production for years and never had any unexplained shutdowns, FWIW.