Storage server – Swapping SAS HBA card for a different model

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Storage server – Swapping SAS HBA card for a different model – A server stack is the collection of software that forms the operational infrastructure on a given machine. In a computing context, a stack is an ordered pile. A server stack is one type of solution stack — an ordered selection of software that makes it possible to complete a particular task. Like in this post about Storage server – Swapping SAS HBA card for a different model was one problem in server stack that need for a solution. Below are some tips in manage your linux server when you find problem about linux, zfs, software-raid, sas, jbod.

TL;DR Server’s original SAS HBA (PCIe card) does not support transparent passthrough, which is desired, as I want the OS to manage the disks (ZFS).

At my company, we have an Intel SSR212MC2 server (spec sheet) with SRCSAS144E RAID controller. The machine is lying around unused, and I was planning to do some experimentation on it before possibly deploying it.

Apparently the SRCSAS144E controller only supports presenting RAID volumes to the OS. Creating twelve single-volume RAID0 groups seemed very inelegant to me, a suspicion confirmed when I realized that the disks wouldn’t be able to be moved to another server (see accepted answer of hba for software raid).

So, if my limited understanding of SAS is correct, I could buy another card (such as this), put it in place of the existing one, and plug the cable coming from the SAS expander into it. At the end of the day, the operating system should then see each individual device, right?

The Linux kernel will need drivers to talk to the card, but I assume there is mainstream support for such a commonplace device. Is there anything else I should watch out for?

You can just use a standard LSI/Avago SAS HBA for this purpose. That’s all that’s necessary.

Since this is an old server… 11 years old, you should see a controller that is period-correct. I’d recommend a used LSI 9211-8i.

No drivers are needed; these are standard MPT Fusion kernel modules. You will need to figure out what to do with the operating system, though. I don’t recommend ZFS for the OS drives. So you may need software RAID for that.

You can configure a set of single disk RAID0 LUNs. Assuming you’ll turn RAID controller cache OFF it should be acceptable equivalent of a pass-thru mode.

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