[dpaton]

😳 I swear I checked both places. When I get the array recovered I’ll check it out.

Thanks for the sanity check….I couldn’t imagine it was anything difficult….

[dpaton]

Jeff-

I believe that Highpoint’s line is broken down like this:
1xxx series: Host based parity (software RAID5), unknown management function for RAID 0 and 1, but probably firmware.
2xxx series: IOP based parity (firmware RAID5), unknown management function for RAID 0 and 1, but probably hardware.
3xxx series: IOC based parity (hardware RAID5), hardwar ebased RAID 0 and 1.

I’m not positive, but after a weekend of reading between the lines on their datasheets, I’m fairly confident of my assessment. In the server I’m scrounging parts for now, I’m probably going with a RR2220, because the price difference between that ($250) and the 3220 ($450) pays for another drive or two in the array.

That said, if Highpoint tells me that the 3220 really does support the 33MHz 64 bit PCI slots in the Gigabit G4 I’m turning into a backup server, I may change my mind and plunk down the extra money for the 3220 and make it a RAID6 box. The old G4 isn’t a fast machine under Leopard, and I need all the hardware help I can get for drives.

[dpaton]

jerky-

For home use the priority list goes something like availability, reliability, size. You first want your data accessable. Then you want it around forever. Finally, you want a lot. Unless you’re doing video or audio production work, or streaming full HD content to your TV, a software RAID5 (or 10, if you have the money) will be plenty I think. 4x 1TB gives you 3TB of RAID5. Should be plenty for almost anyone

There are 3 basic ways to do RAID5 and RAID6 parity calculations:
software
firmware
hardware

The first, software, uses the host CPU to do the math. Generally this is a metric f-ton of XOR statements at a very low level to get the parity bytes, and unfortunately, most CPUs are busy doing other things more important than pile and piles of streaming XORs from a disk controller. This is by far the most common RAID5 implementation in the sub-$1kUS card category.

The second, firmware, does the work on the card using an onboard general purpose processor, or using the (normall present) PCI interface chip, and can actually be worse than host-based parity calculation, if the implementation is poor. This isn’t seen very often, but I’ve heard a few cards do have it (RR2220). Don’t quote me on that though. I have no verification that it exists on any card for Macs.

The final, hardware, is the best option, and until the last few years (relatively speaking) was the only viable way to get RAID5 or RAID6 done. This uses a specifically crafted IO processor (like the Intel unit on the RR3220) to perform all of the parity math, and sometimes offloading other storage related processing as well. It’s fast, and generally is about +35 awesome over any other solution. This is how server grade hardware is designed.

[dpaton]

[QUOTE][u]Quote by: stepansae[/u][p]
Im using this array for network home directories of about 700 users. I have noticed that Rocket Raid performs satifactory for video aplications (final cut), but multiple read and write situations lack performance. XRaid in my scenario performs better (we have some campuses with Xraid, hence the comparison).[/p][/QUOTE]

Point taken. I’ve only ever used the RAIDs in my care for a few users at once, never for hundreds. That said, I firmly believe the bottleneck is in the software handling of the RAID5 parity data calculations, and a card with a dedicated processor for such would be a decent candidate for consideration. I haven’t personally tested any however.

[dpaton]

I’ve used the 1820A for a while and wasn’t thrilled with it’s performance vs more expensive cards, but for what I paid, I couldn’t complain. Under RAID5, the CPU does all the parity calculation, which can be significant. The 3220 has an onboard IO processor, and though I don’t have one yet, I have played with one, and it’s RAID5 and RAID6 performance is significantly better than the other cards on the class of G4 systems I administer.

I think the 2220 and a few others offer firmware RAID5, which is faster than the software RAID5 I’ve been using, but the big daddy is hardware RAID5 processing, and that’s only available on a few cards for the Mac, with the RR3220 being the cheapest and most accessable I’m aware of.

For what it’s worth, the 2220 with fast disks is pretty speedy:

[url]http://www.barefeats.com/hard53.html[/url]

[dpaton]

OK, the fix worked fine but with one interesting quirk. The system accounts were restored just fine, as was the general admin account “Administrator”), but the user accounts on the machine (3) all had corrupted passwords that had to be reset from the admin account via the accounts prefpane. It also took a few restarts of the services to get them all up and running again, which was unusual, but things seem stable for now. I’ve got a backup running now, and I’ll be spending some quality audit time with the system this weekend to see if any weirdness crept in, but it seems to be up and happy again.

Thanks

-dave

[dpaton]

Thanks for the KB#…I spent a good half hour scouring the KB on Saturday morning, looking for something about nidb backups, but for some reason my search-fu was not strong. I’ll give it a shot this afternoon.

-dave

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