Management and Web applications servers

Question

I currently have a web infrastructure on amazon ec2, with a loadbalancer and three servers apache with a php application on it.

And my database is on amazon RDS.

I am looking for an application which allows me to manage my apache servers and to facilitate the deployment of an update on this three servers.

For example if I want to deploy an update on one of these servers, it can be useful to migrate the actives sessions on another server during the update.

Do you know any application which allow this kind of feature ?

Answer 1

The philosophy behind AWS is one way; that is you can create an 'AMI' and create many instances of it. The setup can get a little complicated depending on how you have your storage.

You can also use old school synchronization technology: rsync

There's also software such as Apache Zookeeper or Puppet

I think you'll find there's no magic bullet - every set up is a little different and that's why a variety of methods exist.

The most painless ones are the most complicated to get started - you mention 'migrate active sessions' - technically that's a design flaw. If you're looking to have a distributed system, you're going to want to store sessions in a way that they can all be accessed from any 'node' (Shared volume or database). Then you can simply remove a node for updating from the loadbalancer and the others will pick up the slack seamlessly.