On Sun, Apr 26, 2015 at 04:04:02PM +1000, Russell Coker wrote:
On Sun, 26 Apr 2015 02:53:40 PM Craig Sanders wrote:
you should be able to tell the HP raid card to use the drives as JBOD or, at worst, set up each drive as a degraded raid-1 drive by itself....then you can run linux software raid on top of that.
Last time I tried this with a HP server there was no way to run drives without having the RAID header. The RAID header tells the RAID controller to treat the disk as a JBOD, but it makes the disk slightly smaller and at a slight offset.
i.e. it can't be done without wiping the original drives. it might be possible to shrink the filesystem and partitions on the orig drives and use gparted to move the partition(s) to make room for the raid offset....but that's a lot of stuffing around - would probably be much less hassle to backup, repartition with the HW raid, and restore. stupid crap like this is one of the reasons why HW raid cards should be avoided. this is an anti-feature that serves onlY HP by locking in customers to their products.
Unless you are going to use ZFS or BTRFS then the HP hardware RAID is a better option.
i disagree with the last part of that. the only time hardware raid is even a reasonable option is when you want to use RAID5/6 *AND* you have a support contract with the HW vendor *AND* can afford to have a second identical raid card sitting idle. that still doesn't make hardware raid a better or even good solution, just a tolerable one. for raid-1 or 10, software raid beats the hell out of HW raid, and ZFS mirrored pairs adds error-checking and correction of data as well as snapshotting and many other useful features. for RAID-5 or RAID-6 linux software raid is better, and ZFS RAID-Z is far superior for the same reasons that ZFS mirroring is superior to RAID-1. IMO, the only reason to use HW raid is if you have no other choice. craig -- craig sanders <cas@taz.net.au>