ReferencePlatforms/Test/UbuntuLinux
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Ubuntu 12.04 based test platform is fully automated.
Reference image (AMI) is created by http://hg.mozilla.org/build/cloud-tools/file/e81d7808fb10/aws/aws_create_ami.py script.
Instances are created by http://hg.mozilla.org/build/cloud-tools/file/e81d7808fb10/aws/aws_create_instance.py script. Example steps to create a staging slave may be found here and here