What's the best way to sync a library on two Seafile servers or more?

Hi all,
I have many clients, each one have his own Seafile server, I looking for a way to share a library on all these servers.
I know that Seafile does not support this, so I ask to you all if someone have a solution to do this.
My first thought was rsync, classic solution, but may be you have better ideas.
let me know !