This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
We are deploying a newer version of a web app to run in the same Tomcat instance (1.4.31) as the existing version. On our development servers, winXP, if the new version encounters a startup problem the production version will start, the new version will not start and Tomcat will run as expected.
On the production server, which is linux, Tomcat seems to 'hang' on the first failure encountered when starting the new app and nothing further happens. Tomcat has to be killed when it enters this state because the management console is also unresponsive. In the application log the last log entry is the exception logged from the new app and there is no further logging. Since we have been doing some database changes the usual error that causes this is Jakarta DBCP connection failure but we have also seen it for a missing class file. So I don't think the error is at the root of the problem but at this point I can't rule out anything.
We don't manage the server that this is happening on so we don't have the usual diagnostic capabilities, all we have are the logs. Since Tomcat is completely unresponsive when this happens there is no way to get a thread trace or stack dump. So I'm looking for any ideas on what may be going on or suggestion as to what to try to get more information about the problem.
We are completely stumped by this, any ideas or suggestions would be appreciated.
We see do an exception being logged. It is always the last log entry. In each case the situation causing the exception was either fixed or out of our control. In the case where the exception was fixed the start-up sequence would no longer stop at that point but if there was another exception the start-up would stop and Tomcat would hang. So the exception condition itself does not seem to be the problem.