On 6/18/20 4:10 PM, John Pierce wrote:
On Thu, Jun 18, 2020 at 1:55 PM Valeri Galtsev galtsev@kicp.uchicago.edu wrote:
Ah, I love your good answer. I remember this from the past:
Why my $20 adaptec RAID card (they were "software" RAID) doesn't work as well (if at all) as your $700 3ware or LSI (megaraid) or Areca card?
actually, I prefer the LSI 'HBA' cards in IT mode, with the raid functionality completely disabled, and use the host OS's storage management, ZFS on FreeBSD or mdraid+lvm on Linux. Only place I would use a 'true' RAID controller would be on a Windows Server as Windows software raid is awful, ok, and on a VMware ESXi server, as its storage management is awful, too. But on that latter, I would MUCH rather use NAS/SAN storage. And on the Windows server, I would much rather it be virtualized.
Well, everybody's mileage varies. If one is going to use zfs, then no hardware RAID can beat that, i.e., zfs ensures data integrity, whereas hardware RAID can sometimes guess, which stripe on which physical drive has corrupt data, but not always. On the other hand, if one refuses to use zfs, as it is owned by Oracle now, so one alleges its future is unpredictable, then it is only a question of "taste", some may argue software RAID is better, others: hardware RAID is better. The last would be me; my argument: hardware RAID has dedicated processing hardware and very short, hence well debugged software as opposed to the whole system that is capable affect software RAID. All in all, I do not suggest everybody accept my argument as correct, as I said, is a question of taste for me. Or, borrowing the phrase of my friend "you go your church, I go mine" ;-)
Anyway, it is distributed file systems now, whenever we go for big storage...
Thanks. Valeri