EC2 Launching

Everyday I launch a lot of EC2 instances as part of a controlled process:

• deploying an application in the Engine Yard Cloud Dashboard
• using the EC2 plugin for the knife cli tool for Opscode Chef

I also wind up running a lot of ad-hoc instances for quick experiments. This required a frustrating multi-step dance:

0. ec2-run-instances
1. highlight and copy the Instance ID
2. wait long enough that networking is provisioned
3. ec2-describe-instances with the pasted id
4. highlight and copy the Public DNS attribute
5. wait long enough that sshd will be available before the connection times out
6. ssh -oForwardAgent=yes -oUserKnownHostsFile=/dev/null -oStrictHostKeyChecking=no -i ~/.ec2/keypair.pem with the pasted hostname

Last week I got to the breaking point during one of these cycles and hacked together a script to launch and log into these one-off instances. The helpful tcp_test_ssh and wait_for_sshd methods are grabbed mostly verbatim from the previously mentioned knife-ec2 plugin.