i have 4 disks, sd[a,b,f,g] of various sizes that I want to 'merge' together. I am using mdadm to achieve this.
my question is, what's the difference between --
mdadm --create /dev/md0 --level=linear --raid-devices=4 /dev/sda /dev/sdb /dev/sdf /dev/sdg
mdadm --create /dev/md0 --level=linear --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdf1 /dev/sdg1
When both work? For some reason (if someone could explain this too, it would be awesome) I lose a lot of disk space as is when I look at /dev/md0 but if I create partitions and then create a linear raid, I end up losing even more space.
So why create partitions at all? Even when I do not have this setup and just want to use a disk, can I just do a mkfs.ext3 /dev/sda ?
Additional stuff - Here's /proc/partitions -
8 0 244140625 sda
8 1 244139008 sda1
8 16 244140625 sdb
8 17 244139008 sdb1
8 80 39063024 sdf
8 81 39061504 sdf1
8 96 156290904 sdg
8 97 156289024 sdg1
WHy are the sizes of my partitions smaller than my disk as listed above?