Jan Johansson a écrit :
We use mdadm to administer our software raid. For (certain) hardware raid there other tools available. Just "apt-cache search raid"...Wait... does mdadm have that built in?Let's rephrase that. Lets say I just did cookiemonster:/mnt/hde1# mdadm --create /dev/md0 --level=5 --raid-devices=2 /dev/hd[cd]1 --auto mdadm: array /dev/md0 started. Which gives me a RAID5 on 2x200GB (That right now really is a RAID1)
Raid5 on n-1 disks is more like raid0....
And I later on would like to add _another_ 200GB disk to that array and turn it into a 400GB RAID5, can mdadm do that?
What you can basically do is build a degraded array (using missing) mdadm -Cv /dev/md0 -l1 -n3 /dev/hdc1 /dev/hdd1 missingIt will be like having raid0 (in terms of security) but will let you move your existing data onto it.
Laurent