I have setup a HA architecture using Autoscaling, load balancer , code deploy.
I have a base-image through which autoscale launch any new instance. This base-image will get outdated with time and I may have to upgrade it.
My confusion is how can I provision this base AMI to install desire version of packages ? and How will I provision the already in-service instances ?
For-example - Currently my base AMI have php5.3 but if in future I need PHP5.5 then how can I provision in-service fleet of EC2 instances and as well as base AMI
I have Chef as provisioning server. So how should I proceed for above problem ?