On 29/06/11 16:20, Mark Rogers wrote:
I have an HP server with on-board RAID, ie it takes two drives and presents them to the O/S as a single drive, but the management of that drive utilises the main CPU not a RAID controller.
Were you considering RAID 0 or RAID 1 here ?
If I use it, how would I be able to detect the RAID status?
Or should I just use software RAID and mdtools?
I'd say there is almost no contest there. Unless we are talking Enterprise quality SAS RAID on large arrays then there is little reason to bother with hardware assisted RAID. Particularly when we are talking about just 2 drives.
For some chipsets there are linux management tools but you still generally get worse performance than md arrays are capable of on decent hardware. Also you are bound to your hardware so if say the mainboard of your server fails then you aren't going to be able to mount the disks until you source another with the same chipset *
(* This isn't actually always strictly true as the kernel softraid actually supports some raid profiles used by some of the more common chipsets and sometimes with raid 1 the individual members look like a standard partition on their own when the mirror is broken.)
lspci reports: 00:11.0 RAID bus controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 SATA Controller [Non-RAID5 mode] (rev 40)
If I decided to move to software RAID, what are my chances of migrating the existing install to RAID without re-installing?
Assuming that you have somewhere to store the data whilst you are repartitioning then I'd say very high.