backups

Hello, i have to migrate a big Centos 5 Openvz VPS on a new Proxmox 4 LXC. My Idea was to create a base Centos5 VPS and than use rsync. ( less downtime ). When i try to create a LXC container Cento5: TASK ERROR: unsupported redhat release 'CentOS release 5.11 (Final)' How can i create a minimal...

So after following this guide on how to get my 2TB to be a secondary drive: http://pve.proxmox.com/wiki/Storage_Model#LVM_Groups_with_Local_Backing I now come and face that it isnt allowing me to let it become a backup drive, it does however allow containers and vms (only in raw image however...