adding new disk to software RAID5

boToo · 02-26-2007, 06:37 AM

Hi all,
I have a opensuse10.2 server with software raid with 3 disks.
my set up is below.
/boot --> raid1 -/md0 -->(160M)
/ --> raid5 -/md1 -->(20G)
swap --> raid0 -/md2 -->(9G)
LVM --> raid5 -/md3,/md4,/md5 -->(270G) , from which I have /home, /downloads,/backups,just for future, when i run out of space, can i add another hard disk, same size as previous 3 disks to my system? I am not sure how my LVM would grow. I need your expert opinion.
Thanks in advance

mastrboy · 02-27-2007, 01:44 AM

as i know you can't expand a raid5 in linux, unless you are using EVMS

reeseslover531 · 02-27-2007, 05:22 AM

yes you can actually expand raid-5 with mdadm version 2.4 or later. The command is mdadm --add /dev/md1 /dev/sdf1 and then mdadm --grow /dev/md1 --raid-devices=4 and of course you will need to replace the /dev/md1 and he /dev/sdf1 with correct information, but that is all. the growing will take quite some time so be patient. Since it is LVM it is very easy to expand the file system and such.