Say I have server A and B that are both running a web server + software to detect web server failure. With this basic setup it would claim the elastic IP address whenever the other server is down.

This is all good and well, but how would I go about syncing data between servers? How would I deal with me uploading files to my 'primary' web server and have the other servers in the load balancing pool have those files as well?

I know there are possibilities like NFS, but I would like to hear from other, experienced, people how they (would) do this.

Thanks in advance,
Arjan