====== Create RAID 5 array using LVM ======

''# apt-get install mdadm''\\
''# apt-get install lvm2''\\

Check existing arrays:\\
''# cat /proc/mdstat''\\

Create RAID 5 array:\\
''# mdadm --create --verbose /dev/md0 --level=5 --raid-devices=3 /dev/sdb /dev/sdc /dev/sde''\\

Check the array exists:\\
''# cat /proc/mdstat''\\
''# mdadm --detail /dev/md0''\\
=> there is an initial phase of reconstruction when an array is created. It is supposedly functional during this time.\\

Make the array a LVM Physical Volume (so it can be used by LVM):\\
''# pvcreate /dev/md0''\\
=> That takes time!\\

Check result:\\
''# pvs''\\
''# pvdisplay''\\

Define a LVM Volume Group consisting of the array (usually on several disks, but we already packed them with RAID so it's just one 'drive'):\\
''# vgcreate vg_data /dev/md0''\\
==> takes time as well!\\

Check result:\\
''# vgdisplay vg_data''\\

Create LVM Volumes on the Volume Group:\\
''# lvcreate -n vol_perso_data -L 350G vg_data''\\
=> use -l instead to give % of available space\\

Check result:\\
''# lvs''\\
''# lvdisplay''\\

We can now use the new Volumes as we would use normal disks!\\
Access is done through ''/dev/vg_data/vol_*''\\

For example, to create ext4 partitions:\\
''# mkfs.ext4 /dev/vg_data/vol_music''\\