Btw xtrabackup is not only backup..

It is obvious thing for me, but I just figured out it may be not common understanding. Xtrabackup is also can be used (not only can, but we actually use it this way) to clone one slave to another, or just setup new slave from the master. And it is done in almost non-blocking way ( true for InnoDB setups) for cloned server. Here is command

When it finished on destination server you run

And you have ready database directory, just copy my.cnf from original server and start mysqld.