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I've got an HP D2700 enclosure that I'm looking to shove some 2.5" SSD drives in. Looking at the prices of HP's SSD drives vs something like an Intel 710 and even something less 'enterprisey', there's quite a difference in price.

I know the HP SSD's will obviously work, but I've heard rumours that buying an Intel/Crucial/whatever SATA SSD, bunging it in an HP 2.5" caddy and putting it in a D2700 won't work.

Is there an enclosure / disk compatibility issue I should watch out for here?

On the one hand, they're all just SATA devices, so the enclosure should treat them all the same. On the other, I'm not particularly well-versed in the various different SSD flavours to know whether there's a good technical reason why one type of drive would work, yet another one wouldn't. I can also imagine that HP are annoying enough to do firmware checks on any disks and have the controller reject those it doesn't like.

For background, the D2700 already has 12x 300GB 10k SAS drives in it, and I was planning on getting 8x 500GB (or thereabouts) SSDs to create another zpool. Whole thing is connected to an HP X1600 running Solaris 11.

Well, I use a D2700 for ZFS storage and worked a bit to get LEDs and sesctl features to work on it. I also have SAS MPxIO multipath running well.

I've done quite a bit of SSD testing on ZFS and with this enclosure.

Here's the lowdown.

• The D2700 is a perfectly-fine JBOD for ZFS.


• You will want to have an HP Smart Array controller handy to update the enclosure firmware to the latest revision.


• LSI controllers are recommended here. I use a pair of LSI 9205-8e for this.


• I have a pile of HP drive caddies and have tested Intel, OCZ, OWC (sandforce), HP (Sandisk/Pliant), Pliant, STEC and Seagate SAS and SATA SSDs for ZFS use.


• I would reserve the D2700 for dual-ported 6G disks, assuming you will use multipathing. If not, you're possibly taking a bandwidth hit due to the oversubscription of the SAS link to the host.


• I tend to leave the SSDs meant for ZIL and L2arc inside of the storage head. Coupled with an LSI 9211-8i, it seems safer.


• The Intel and Sandforce-based SATA SSDs were fine in the chassis. No temperature probe issues or anything.


• The HP SAS SSDs (Sandisk/Pliant) require a deep queue that ZFS really can't take advantage of. They are not good pool or cache disks.


• STEC is great with LSI controllers and ZFS... except for price... They are also incompatible with Smart Array P410 controllers. Weird. I have an open ticket with STEC for that.

Which controllers are you using? I probably have detailed data for the combination you have.

Any drive should "work" but you will need to carefully weigh the pros and cons of using unsupported components in a production system. Companies like Dell and HP can get away with demanding 300-400% profit margins on server drives because they have you over a barrel if you need warranty/contract support and they find unsupported hardware in your array. Are you prepared to be the final point of escalation when something goes wrong?

If you are already using ZFS, take a long look at the possibility of deploying SSDs as L2ARC and ZIL instead of as a separate zpool. Properly configured, this type of caching can deliver SSD-like performance on a spindle-based array, at a fraction of the cost of exclusively solid state storage.

Properly configured, a ZFS SAN built on an array of 2TB 7200rpm SAS drives with even the old Intel X25E drives for ZIL and X25M drives for L2ARC will run circles around name-brand proprietary SAN appliances.

Be sure that your ZIL device is SLC flash. It doesn't have to be big; a 20GB SLC drive like the Intel 313 series, which happens to be designed for use as cache, would work great. L2ARC can be MLC.

Any time you use MLC flash in an enterprise application, consider selecting a drive that will allow you to track wear percentage via SMART, such as the Intel 320 series. Note that these drives also have a 5-year warranty if you buy the retail box version, so think twice about buying the OEM version just to save five bucks. The warranty is void if you exceed the design write endurance, which is part of why we normally use these for L2ARC but not ZIL.

First, the enclosure firmware may (and surely will) notice non-HP-branded disks, but in fact it won't impact you too much. I doubt HP hardware will reject your drives (never seen that on HP ever before), so I'd give it a try.

But, when it comes to any updates (mainly, new enclosure firmware), HP will fix issues with their branded hardware, not with any no-name one.

Dispute the price, HP-labeled hardware is much robust (have seen several non-enterprise SSDs died after being loaded in enterprise environment - check if you want to pay for the extra risk, or at least ALWAYS backup), so it may worth to over-pay.

You may also want to consider FusionIO cards, as SATA bandwidth (not only disk-to-controller path, but also keep in mind controller-to-bus-to-CPU path) may impact you while PCI-E cards can be faster.

If it's not on the list of supported drives (configuration information, step 4), don't install it. It may or may not work, but it would be a fairly expensive experiment if it didn't work in such a way that something broke.

They have five SSD drives listed for this box, 2 SLC and three MLC. SLC last longer, but tend to be more expensive.