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Mount the server filesystem via smbmount, sshfs, nfs, ... Let's assume the backup storage folder is available as /media/server/urbackup. Forum post for more detailed instructions.
Restore MBR
To restore the mbr run following command (if you want to restore to /dev/sda). On the restore cd you first have to become root (sudo su) and then change to the home folder (cd /root):
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