I recently installed Debian Wheezy and let the installer guide partition the disk using a whole partition with encryption (LVM). Later on I've added four disks and setup RAID5 on them (using mdadm). ...
I've got a server with 3 sata hard drives. Each has 2 partitions: one small is part of /dev/md0, a raid1 array (/boot), rest is part of a raid5 array (/dev/md1), which is an lvm physical volume. ...