How to deploy and manage java programs across servers?

I wrote some java server side processing apps that have been running on a couple se开发者_运维百科rvers but will be expanded to 20 servers. Right now I'm just using ant scripts to deploy my jar to servers via rsync and then using screen to start the jobs.

This requires me to ssh in and restart the jobs each time I deploy new code, once I go to 20 servers this will become unmanageable.

I'm pretty new to java, is there a standard way of deploying across servers along with restarting jobs afterwards? Ideally I'm looking for a free and easy solution.

thanks

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It looks you would benefit from using OSGi. You would need to migrate your application into an OSGi bundle but it looks it would be worth the pain. Equinox, Knopflerfish and Felix are open source implementations. This link could be useful too.

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Twitter uses bittorrent and murder

Going with what works well for others seems to be a really good start! Read about murder here

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Maybe it's an option to enter into system administration domain and evaluate remote configuration management tools like Chef or Puppet for the task.

Not sure if it fulfills the 'easy' condition, though.