This is a n00b question but when you have two LSI controllers can you link them to form one giant spanned RAID array accross both?I currently have 10 840 Pro (256GB) connected to one machine. The remaining 6 SSDs will arrive later today.
Currently connected to 2 x LSI 2308 HBA's.
Don't know about the Firmware capabilities of the controllers, but spanning Raids in the OS over multiple controllers is no problem. In Raid0, the 16 Samsungs deliver close to 8 GB/sec read and 7,2 GB/s write.This is a n00b question but when you have two LSI controllers can you link them to form one giant spanned RAID array accross both?
Thanks Andy. Does anyone know if two LSI 9271-8i cards will allow to span a RAID array accross both cards?Don't know about the Firmware capabilities of the controllers, but spanning Raids in the OS over multiple controllers is no problem. In Raid0, the 16 Samsungs deliver close to 8 GB/sec read and 7,2 GB/s write.
Nope, no spanning with LSI over controllers.Thanks Andy. Does anyone know if two LSI 9271-8i cards will allow to span a RAID array accross both cards?
I could probably get the hardware (although don't have an Adaptec contact.) Might be at the point where I'd need help doing the testing.Adaptec has 16 ports natively, this is why they are faster than 8 port LSI cards. The HBA is stupid cheap, but for SSD the 71605e is not bad price.
RAID 1/1E/10 - Raid 1E is like raid-5 without parity on odd drives. Even drives usually are just considered Raid 10(1+0) but don't have to be.
3 drive Raid 1E requires no crc/checksum , it just moves the blocks around like
1 2 3
3 1 2
2 3 1
Not sure if that's a good idea with SSD due to strip size but if you modified only one block, and the other blocks did not change, the SSD would probably disregard the write. Raid-10 is nice but does have similar write amplification with drive redundant block skips, raid-1 doesn't scale as much as-is but reduces write amplification of all 3.
16 SAS ports $370 [software raid] - question is - can you cross flash it? the 71605e has only 256 meg cache. I wonder what makes it jbod only since all Adaptec cards can do IT and IR at the same time.
Heck my old SAS 6/IR 1068E presents any non-raid non-spare drive as JBOD which was throwing me off since many LSI cards ban the feature out of the box.
I'd like to see a STH comparison of 71605q -> 9271 w/cc, 71605e -> LSI 2308, 71605h -> LSI 2308 . Or whatever is street price similar.
The hp OEM P420/1GB FBWC ($249 ! new ! limited deal ) kicked mucho butt. It outruns the 9266 w/fastpath+cc 2.0 and has its own cachecade 1 thats performs flawlessly with the same great UI.
Just finished building some servers with four Samsung 840 Pro 512GB. I used Intel RS25DB080 which is the same as 9270-8i.
It seems as though the 4kQD32 write throughputs of both of your setups are lower than what they ought to be.In the meanwhile.
4 x 256GB Samsung 840 Pro, connected to an LSI 9207-8i controller.
Raid5: via SW in WS2012
I think it is just an anti-LSI-istAre you saying that there's an issue with Samsung 840 Pro as a Cachecade device or as a RAID set with 9270? Can you benefit or does anyone use Cachecade with straight SSD drives as RAID? I can see how I might want Fastpath for all SSDs but not sure if there's any benefit with Cachecade with all SSD RAID sets. I thought the Cachecade was for spinning drives...