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Introduction

The Cargo Daemon is a Web-based application that uses the Cargo API to configure, start and stop containers on a remote machine.

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It can be accessed using a browser-based UI, via Java API or Maven2 plugin.

Why use the Cargo Daemon?

Most web containers (e.g. Tomcat, Jetty) provide built-in remote deployment facilities already, so why use the Cargo Daemon?

All of the remote deployment facilities that keep the JVM alive will eventually suffer from the dreaded "java.lang.OutOfMemoryError: PermGen space" exception if something in the web application is leaking memory.
Most web containers try their best to track down these 'dead' objects and forcefully remove them, but it does not always succeed to reclaim the memory. With a leaking web application,
the available memory starts to shrink after each redeploy, and eventually the memory is exhausted.
The only solution to this is to kill the JVM, and restart it. And that is exactly what the Cargo Daemon tries to manage. It will try to shutdown the web application cleanly, but if that fails it will forcefully kill the JVM.
It is the only way to guarantee that a new version of your web application always starts when you want it to.

Table of Contents

The documentatation for the Cargo Daemon includes:

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