Tomcat quirks

In recent weeks, we've had problems with our company's servers going down because of power problems at our colocation provider. As a result, the fact that Tomcat hadn't been properly configured to boot at startup had really burned us. Consequentially, I've been spending the past few days troubleshooting why the servers wouldn't startup, and ensuring that they do come up properly at boot time in future. The following are some of the things I've run across.

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  The JAVA_HOME and JRE_HOME variables must be set. If they're not, then Tomcat won't start, at least on Ubuntu Gutsy Gibbon Server. This is a problem I encountered with the default installation of JIRA on one of our production servers.
  


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  When using EhCache with Hibernate, the tmp directories don't get deleted, regardless of whether or not Tomcat is shutdown properly. This will block the container from starting up again, so these temp files must be deleted. I encountered this problem with my own applications.