[CentOS] CentOS 6 x64 - Changing /var folder to raid 1 disk after install

Hello,

I have fresh install CentOS 6 x64 running on my server. I have a raid
1 drive 3 tb ready to be mounted. I want to mount this as var folder,
could achive this but after reboot, server didn't start, maybe i had
problem with command cp -rf.

Is this possible to do in a proper manner, with what commands?
I used rsync and diff game me like 10+ output.

Best regards