I was wondering the best way to share files across a set of servers. At the moment I am hosting them on rackspace cloud files (2ms from london dc) but they are still quite slow. I am considering sticking them in mysql as a blob and loading them but it will make my database backups go from a couple of mega bytes to giga bytes.

Can any one suggest a way to achieve this with a couple of linodes in a single data center? I don't mind pushing backups off site but would like to try and get the loading as close to normal disk performance as possible.

If you just want a 2-way rsync unison does the job.

http://www.cis.upenn.edu/~bcpierce/unison/

I looked at unison but have managed to implement s3fs in cached mode which seems to be working very well.