4 x 3 TB SAS HDs in N36L recomendations

[netamego]

Hi,

I am thinking in use a N36L HP Microserver with four 3 TB SAS HDs in RAID 1. N36L have SAS 8087 connector in motherboard, i don't know why but seems a SAS controller is necesary anyway. I am thinking in LSI 9207 or HP P410 because boths seems to support 3 TB HDs. Then I have read that FreeNAS works better with software raid (done by FreeNAS) than hardware raid. Also, i don't know why because N36L is not a very powerfull machine and i think that software raid is very CPU intensive. As you see I'm full of doubts and I am very lost. Are there someone with similar configuration that can help me?. What its the cheapest configuration that could work?. What is a must are my four SAS 3 TB HDs.

Thanks a lot.

 

[jgreco]

Imagine for a minute that your hardware RAID controller could not detect problems with the member disks in an array.

Hopefully you'd say that is absolutely crazy. Because, well, it's absolutely crazy.

With ZFS, ZFS itself IS your storage controller. If you place a hardware RAID controller between ZFS and the disks, you are placing something in the path of your storage controller, making ZFS unable to detect problems with the member disks in the array. Worse, you are crippling ZFS's magical ability to remediate errors, by removing access to the redundancy data that allows ZFS data protection to work.

Using a hardware RAID controller with ZFS is therefore also absolutely crazy.

And no matter what you think of the power of the N36L and that you believe "software raid is very CPU intensive," you're basically just wrong. The limiting factor on an N36L is going to be the gigabit ethernet port. Bitwise operations on modern CPU's are VERY fast. Doubt me? Look up what CPU is on your RAID controller and see what the throughput numbers are like...

I don't care to rip apart an N40L right now to look at it but I suspect that there's probably space in there for a standard IT-mode HBA. You need to crossflash one of the typical HBA's, M1015, H200, H310, 9211-8i, etc., to IT mode with LSI firmware. Plug the drive array into that. The HBA supports SAS and then it's very likely the N36L will be able to work like that.

 

[netamego]

Thanks a lot for your reply. Finally i bought a N40L with 8GB RAM. Have someone this HP Microserver working with FreeNAS and SAS HDs?. What is your config?. What is the cheapest HBA that can work with 3TB SAS HDs and in IT mode to made "compatible" wit ZFS?. Thanks a lot.

 

[jgreco]

Thanks a lot for your reply. Finally i bought a N40L with 8GB RAM. Have someone this HP Microserver working with FreeNAS and SAS HDs?. What is your config?. What is the cheapest HBA that can work with 3TB SAS HDs and in IT mode to made "compatible" wit ZFS?. Thanks a lot.

Years ago I outfitted an N40L here with an IBM BR10i controller. Not for the bays, but for some add-on boot SSD's. That controller won't support 3TB HDD's.

I stand by previous suggestion: You need to crossflash one of the typical HBA's, M1015, H200, H310, 9211-8i, etc., to IT mode with LSI firmware. Plug the drive array into that. The HBA supports SAS and then it's very likely the N36L will be able to work like that.

As I haven't done it, I can't say whether or not you might run into other problems like cabling.