seamless redeploy for java web application

Question

I am working at a startup, we are just about to roll out our first beta. Knowing that we will be having a good number of users, we want to have seamlessly deployment when we are adding new features.

I have worked with windows azure before, and I know they support seamless deployment, so I did some googling and cloudbees was the first result.

So the question is, with what we have now (geronimo server, rackspace hosting), is it possible to seamlessly redeploy a java web application? If so, how?

Are there other alternative solution, such as using another hosting provider or use a different web server? (Because it is a startup, it would be beneficial if the answer keeps scalability in mind)

Answer 1

I have heard Glassfish has such feature, the reference probably ment this (Glassfish 3.x redeploy command) : http://docs.oracle.com/cd/E19798-01/821-1758/6nmnj7q1h/index.html

Answer 2

There are a lot of methods for doing this in the java world. If you don't use sessions (or use shared sessions between app servers) you can do a rolling stop/deploy/start of your appservers, taking 1 offline at a time and using a load balancer to ensure that traffic goes to the other servers.

Answer 3

If with a seamless redeploy, you mean an upgrade of your application without any downtime or restarting of your server, LiveRebel might be something to look at.

See http://zeroturnaround.com/liverebel