Best 20+ Disk Raid Controller

[Butcher9_9]

I currently have an Adaptec 51645 Raid controller (about 6-8 years old I think) with 20 HDDs spread across 3 Raid 5 arrays . I have been having a few issues with it (dropped drives, system lockups when transferring to arrays and once an error saying the firmware could not be loaded) so I think its time for a new controller.

So my question is whats the best value 20+ controller out there with raid 5 support or greater?

I have been looking at the Adapter 72405 which seems good its just a shame that the 8 series don't offer a high port. I have also looked at the Acera ARC-1284Ml-24 but its only PCI-E 2 and since my current system only has a 4x port free PCI-E 3 would be great.

PS, I use this PC as an all in one LAN rig so using a HBA and Unix base software raid (while a nice idea) is not really on the cards.

 

[Blue Fox]

Best value? Get an 8 port controller and then use a SAS expander to get the rest. Also, just because the card isn't PCIe 3.0, doesn't really make a difference. The processor on the RAID card is usually going to be limited well below PCIe 3.0 bandwidth for parity calculations (let alone PCIe 2.0). If you want the highest performance, an Areca 1883i or one of the later generation LSI ones would be the ones to get. For value, just get something a couple generations older.

Also be prepared to get hammered with people telling you to use ZFS regardless and avoiding RAID 5.

 

[Butcher9_9]

Thanks for the reply, I'll look into a Card and Expander, assuming its a lot cheaper that might work out well. the main reason i have never gone down that path before is that everyone i know has had issues with drive compatibility in expander/controller environments where as I have not.

Quick question though. with expanders do they roll back to the lowest common connectivity type. As in if I get a SAS 12G controller and expander but use SATA 3 drives would it roll back to 6G connectivity between the expander and controller? The reason I ask is that if I get a 4 port Adapter 8 series card that should give me 48Gbits enough of interconnectivity which is a fair chunk, 24 less so but still doable I guess.

 

[_Gea]

I currently have an Adaptec 51645 Raid controller (about 6-8 years old I think) with 20 HDDs spread across 3 Raid 5 arrays . I have been having a few issues with it (dropped drives, system lockups when transferring to arrays and once an error saying the firmware could not be loaded) so I think its time for a new controller.

So my question is whats the best value 20+ controller out there with raid 5 support or greater?

I have been looking at the Adapter 72405 which seems good its just a shame that the 8 series don't offer a high port. I have also looked at the Acera ARC-1284Ml-24 but its only PCI-E 2 and since my current system only has a 4x port free PCI-E 3 would be great.

PS, I use this PC as an all in one LAN rig so using a HBA and Unix base software raid (while a nice idea) is not really on the cards.

My general advice for many large disks is
- avoid Raid-5, use double parity Raid like Raid-6 or Z2
- Sata disks behind an Expander can give problems (yes it works but there are reports that a bad Sata disk can block the whole Expander with a reboot needed to get ist working again. This is not the case with SAS disks)
- prefer Software Raid over Hardware Raid especially if you can use newer filesystems.

As you said, Unix based Software Raid (ZFS) is not an option, I asume this is a Windows setup.
While Microsoft offers the 3rd gen filesysystem ReFS for a Software Raid with Storage Spaces and similar features like ZFS, mainly CopyOnWrite (crash resistent) and metadata with optional data checksums, I would be undecided to use Software Spaces with ReFS or Raid-6 with ReFS or NTFS, mainly because Storage Spaces handling is quite complicated and known to be slow.

With ReFS over Raid-6 you can detect file errors due checksums but would not be able to repair data as the Raidcontroller is not aware of these problems, only the OS/Filesystem.

 

[Blue Fox]

Thanks for the reply, I'll look into a Card and Expander, assuming its a lot cheaper that might work out well. the main reason i have never gone down that path before is that everyone i know has had issues with drive compatibility in expander/controller environments where as I have not.

Quick question though. with expanders do they roll back to the lowest common connectivity type. As in if I get a SAS 12G controller and expander but use SATA 3 drives would it roll back to 6G connectivity between the expander and controller? The reason I ask is that if I get a 4 port Adapter 8 series card that should give me 48Gbits enough of interconnectivity which is a fair chunk, 24 less so but still doable I guess.

The link between the expander and controller will stay at the higher speed fortunately. 24gbit is still far more than your disks are capable of. They're going to presumably do about 150MB/s tops each, so half the available bandwidth if they're all being utilized concurrently. Also, you can use 8 lanes for connectivity (ie both ports) instead of just 4 if you want. I'd probably get the Intel expander if I were you (RES3FV288 for example).

 

[Butcher9_9]

My general advice for many large disks is
- avoid Raid-5, use double parity Raid like Raid-6 or Z2
- Sata disks behind an Expander can give problems (yes it works but there are reports that a bad Sata disk can block the whole Expander with a reboot needed to get ist working again. This is not the case with SAS disks)
- prefer Software Raid over Hardware Raid especially if you can use newer filesystems.

As you said, Unix based Software Raid (ZFS) is not an option, I asume this is a Windows setup.
While Microsoft offers the 3rd gen filesysystem ReFS for a Software Raid with Storage Spaces and similar features like ZFS, mainly CopyOnWrite (crash resistent) and metadata with optional data checksums, I would be undecided to use Software Spaces with ReFS or Raid-6 with ReFS or NTFS, mainly because Storage Spaces handling is quite complicated and known to be slow.

With ReFS over Raid-6 you can detect file errors due checksums but would not be able to repair data as the Raidcontroller is not aware of these problems, only the OS/Filesystem.

Thanks, that was the experience that my friends have had, Expanders seems to just been too much of a hassle.

Yeah, I'm running Win10 Pro at the moment as it provides the best gaming compatibility (server OS's tend to be a pain), I have looked into ReFS however it seems to be fairly immature at the moment with little support for advanced Raid lvls and I have been told that windows raid has very bad performance in Raid 5 or 6 so i guess I'm stuck with what I have now (hardware controller with native 20+ disk support)

as far as Raid6/Z2 goes, my data is not super important so Raid 5 has always severed me well and I have full backs of my 100TB so its not really and issue anyway.

 

[Butcher9_9]

Hi Guys

Any experiences with the Areca ACR-1883IX-24?

Seems to be on par with the Adaptec 8 Series but with 24 ports.

Also i'm assuming my arrays will not migrate directly across to that card as they would with Adaptec.


Edit
Turns out the Areca cards are very expensive in Australia so I made the jump and got the 72405, got a good deal but i have to wait a few weeks which is a pain as my main array is dead and my current card is not playing nice so i have to wait before i can restore it.