There are a couple issues I’ve run into recently with AWS EC2 and CentOS that I can’t explain:

1. EC2 Micro instances will sometimes not reboot, or take very long to do so. A work around is to use a small instance anytime you think you’ll need to reboot your instances for any reason.

2. EBS volumes running EXT3 or EXT4 will occasionally hang for no apparent reason, and the hung process is practically un-killable. After spending days trying to figure out why my python buildout script was occasionally hanging mid-buildout, I came across an article suggesting I use XFS. Using XFS seems to have solved this issue. Fingers crossed, but no buildout hangs yet.