The interesting part which I couldn’t find onto your webpages / in Google search is howto setup “bests” instances.
I was very surprised when I found these settings - but I cannot find any informations about them:
root@piwik-admin:/etc/piwik# grep -B 1 aws global.ini.php
; access key and secret as listed in AWS -> IAM -> Users
aws_accesskey = ""
aws_secret = “”
; key pair name as listed in AWS -> EC2 -> Key Pairs. Key name should be different per user.
aws_keyname = “”
; PEM file can be downloaded after creating a new key pair in AWS -> EC2 -> Key Pairs
aws_pem_file = ""
aws_securitygroups = "default"
aws_region = "us-east-1"
aws_ami = "ami-ac24bac4"
aws_instance_type = “c3.large”
From content it seems that there could be setup an administrative instance with IAM rule attached which can autoscale it’s nodes / registering them perhaps also behind ELBs ?