Question

Is it possible to determine if a Tomcat has started successfully AND all of the webapps deployed to it have also started successfully?

Of course I can trawl the Tomcat’s log file, but is there an easier way?

I need to be able to monitor the tomcat programmatically, since I need to start about 15 Tomcats (they can be started in serial). I’m not afraid to write a bash script and monitor the output of each log looking for the success message or any error messages, but surely there’s a more elegant way?

Answer 1

The most accurate way to ensure a service is up and running is to hit that service with a client.

In the case of WebApps on Tomkat, a cron job that hits some page of each app that indicates the application’s status (up, down, etc.) is the best way to do this.

I say it’s the best way for a number of reasons:

1. It can use the same ports and protocols the application itself uses
2. It allows you to check “on demand”, so if your heartbeat application needs to “beat faster” to catch failures faster, you can turn it up
3. It allows you to have the heartbeat process on another server, to protect against the server you are testing crashing and taking the heartbeat notification process down with it
4. It allows you to scale out easily, both the heartbeat process, and the number of servers you have to hit.
5. It allows each application to define a “status” page that the heartbeat process can hit and scan to check a number of things internal to the application, if needed, without needing to do the same thing, but by looking at log files.