In this post I’ll run through the quick steps required to update your AWS Auto-Scaling group to use a new EC2 AMI. This post builds on the guide covered in my earlier post on setting up an Auto scaling group for an elastic load balancer, which in turn was built on the WordPress clustering guide. You could say this is part 3 in a rather long-running series.
There’s not much too this process thankfully.
Step 1: Create your new AMI
The easiest way I have found to do this is actually via the EC2 console. All I do is start a new instance on my current AMI, log into it and make any changes required (install/update packages etc) and then from the EC2 console, select the instance.
You don’t often need to log into the slave nodes, so if you need a refresher on how to do it, this command is all you should need:
ssh -i path/to/your/key.pem email@example.com