Comment 16 for bug 615545

Agree with Eric- this will be less expensive in the long run, though potential to use CDN for the mirror is intriguing.

One last point in support of CNAMEs- in case there is unease with relying on the CNAME solution (as Canonical does not control routing in EC2), rest assured that this method is supported and recommended by EC2 engineering team and is used by virtually every large deployment on EC2.

One additional benefit is that, with a low time-to-live value, you can easily replace a troubled repo server with a simple "ec2-associate-elastic-ip" command.