SAS card to external enclosure?

[paradoxiom]

Currently I use an Icy Dock https://www.amazon.co.uk/Icy-Dock-Vortex-MB074SP-B-3-5-inch/dp/B00GSQMYY0/ as an external cage.

But a lot of the time I am getting that pool can no be imported because I am assuming a cable got knocked or something at the back of the hard drives, so what I'm asking / looking for is essentially something like the Icy Dock only less.. janky?

Something like this:
https://www.amazon.co.uk/dp/B075ZXQL4J/ref=psdc_949408031_t5_B002BLZ8TO
Looks a lot better to me. But of course.. usb 3 external port so no point.

Acually looking for something with capacity for 8x drives if anyone has any suggestions.

Thanks in advance,
simon

 

[Chris Moore]

This is what you want:
https://www.amazon.co.uk/RocketStor...=UTF8&qid=1533317959&sr=1-7&keywords=sas+jbod
You will need a SAS controller and cables to go with it.
This is the kind of cable and you will need two:
https://www.amazon.co.uk/CableCreat...8&qid=1533318040&sr=1-8&keywords=SAS+external
This is the kind of interface card:
https://www.amazon.co.uk/0J53X3-Del...d=1533318087&sr=1-4&keywords=SAS+HBA+external
With an enclosure that supports SAS Expander technology, you can connect more drives. The controller is good for 256 if I recall correctly.

 

[Chris Moore]

PS. If you wanted to cobble this together with used parts, it might be less expensive.

 

[paradoxiom]

This is what you want:
https://www.amazon.co.uk/RocketStor...=UTF8&qid=1533317959&sr=1-7&keywords=sas+jbod
You will need a SAS controller and cables to go with it.
This is the kind of cable and you will need two:
https://www.amazon.co.uk/CableCreat...8&qid=1533318040&sr=1-8&keywords=SAS+external
This is the kind of interface card:
https://www.amazon.co.uk/0J53X3-Del...d=1533318087&sr=1-4&keywords=SAS+HBA+external
With an enclosure that supports SAS Expander technology, you can connect more drives. The controller is good for 256 if I recall correctly.

thanks,

£547.00
for the 8-bay enclosure, and hardly in stock anyway? I feel like there is a huse gap in the market here that the Gen8 filled but doesn't quite bridge the gap. Anyone else?

 

[HoneyBadger]

Enterprise-grade SAS JBOD units like the Lenovo SA120, HP D2600, and EMC KTN-STL3 are available relatively inexpensively, but they rely on a SAS expander chip and I don't recommend using SATA behind those without using interposers; which would eat into any savings you realize from getting the cheaper "enterprise" JBOD. They're also loud, hot, and power-hungry.

You could try building one yourself, by putting multiple IcyDock 3.5"-into-5.25" cages into an ATX case, doing internal wiring using SFF-8087 breakout cables, and finally an SFF-8087 to SFF-8088 bracket in the back to connect to an HBA - but again, that seems like it will add up in cost quickly.

It really feels like there's an untapped market here for an 8-bay external SAS-attached JBOD unit (that isn't hilariously overpriced like the one linked above)

 

[Chris Moore]

It really feels like there's an untapped market here for an 8-bay external SAS-attached JBOD unit (that isn't hilariously overpriced like the one linked above)

Sans Digital used to make one that was priced around $375, but I can't find anyone that has it in stock.

There is this one at PC Pitstop, and it is about the chapest I have found at only $298:
https://www.pc-pitstop.com/sata_enclosures/scsat84xt.asp

15 bays in this one: https://www.pc-pitstop.com/sas_cables_enclosures/15-bay-trayless-tower-jbod.asp

The problem is, the hardware needed to build it right costs, even if you buy parts and build it yourself, you would be hard pressed to build it right and not spend as much. Then, if you cut corners to save on the cost, it could cut into reliability.

 

[NaCl]

As an alternative Norco makes some rackable JBOD SAS units(DS24E). I have 4 and an RP-4224. The latter is meant to house the server bits itself and only contains drive trays and backplanes.

I also recommend the Broadcom/Avago/LSI 930x-xx series SAS HBAs.

Sent from my Pixel 2 XL using Tapatalk

 

[Chris Moore]

Here is the one I was looking for from Sans Digital. It even comes with the SAS cables:
https://www.newegg.com/Product/Product.aspx?Item=N82E16816111472

 

[Chris Moore]

I feel like there is a huse gap in the market here that the Gen8 filled but doesn't quite bridge the gap. Anyone else?

For the price, it is very hard to beat something like this used enterprise gear:
https://www.ebay.com/itm/SUPERMICRO...S2-826EL2-2-X-PWS-1K21P-1R-12BAY/222338813833
You just have to shop around for what you are after. It is very difficult to fine quality gear that is going to work reliably and not pay for it because, supply and demand. If there was not demand, the price would drop or they would stop making it.

 

[Arwen]

One thing to remember, is that even if you use a SAS controller card, unless it's talking to SAS disks or a SAS expander, it runs SATA protocol from the HBA chip to the disks. So keep your cables SHORT and use high quality cables. Don't forget that their is internal cable length inside each disk chassis and generally at least 1 extra connector inside, (sometimes even 2 or 3). These reduce the overall reliable external cable length. Last, for eSATA enclosures, (even if they use SAS type external connectors), you need one SAS / SATA lane per disk.

Of course, if the disk chassis has a SAS expander chip, it's a whole new ball game. You only need 1 SAS lane per SAS expander, (though 4 SAS lanes is more common).

 

[HoneyBadger]

As an addendum to what @Arwen said above, some external drive cages use SATA port multiplication. These are bad for ZFS. Don't use them.

Others actually implement some manner of RAID within themselves and use DIP switches or similar jumpers to present the drives as a single volume. These are absolutely abysmal for ZFS. Don't use them.

Edit: Apparently this isn't a problem with SAS2 expanders, it was primarily a SAS1 thing and isn't relevant anymore. Finally, using SATA behind a SAS expander can come with its own set of reliability gremlins, including situations where a failing or intermittently buggy SATA cable/connection causes the whole backplane/expander to reset. Using SATA-to-SAS interposer cards is strongly recommended, but given the added cost of this hardware the cost to go with NL-SAS devices starts to be almost negligible.

 

[Chris Moore]

Finally, using SATA behind a SAS expander can come with its own set of reliability gremlins

You keep saying this, but I have not seen any issues. I have a server at work with four SAS expander shelves fully populated with SATA drives (64 of them) and I have two servers at home (one 48 bay, one 24 bay) using SAS expanders with SATA drives and I have not had any issues. Can you please explain what hardware you experienced this with because it might be hardware specific.

 

[CraigD]

You could try building one yourself, by putting multiple IcyDock 3.5"-into-5.25" cages into an ATX case, doing internal wiring using SFF-8087 breakout cables, and finally an SFF-8087 to SFF-8088 bracket in the back to connect to an HBA - but again, that seems like it will add up in cost quickly.

This is my recommendation

It is not that hard my JBOD can hold 20 drives, I was using cheap cages but now use Kingwin 5 drive enclosures, a SAS Expander, a PCIe riser, and a PSU jumper, PSU, a large case, 8087 to 8088 pass thru, an 8088 cable, and a reverse breakout cable (you can use a 8087 cable from your SAS card) and some 8087 to sata cables

Have Fun
JBOD is on the right

 

[HoneyBadger]

You keep saying this, but I have not seen any issues ... Can you please explain what hardware you experienced this with because it might be hardware specific.

A variety of SAS1 expanders. The issue may be resolved as of SAS2 but I'm erring on the side of caution.

What happened is that failing SATA drives or marginal cable connectivity caused the entire backplane to reset itself in an attempt to get the drive back online - it would work for a short time and then trigger another reset. Eventually the LSI driver/ZFS gets fed up and goes "screw this, all of these drives are failed" and pool goes offline.

A drive that went stone dead immediately would fail gracefully and be offlined, it was the "hey I'm here, whoops I'm gone, repeat" that would do greater damage. Never had a failing SAS drive knock an expander down.

 

[Chris Moore]

A variety of SAS1 expanders. The issue may be resolved as of SAS2 but I'm erring on the side of caution.

I have only tried with SAS2 expanders and I know that many SAS1 expanders were not all they could have been. I have a fairly harrow range of experience because I have only three brands of equipment but the results have been good so far. The disk shelves at work have been in service for around 3 years with no trouble at all and we have had around 7 (that I can recall) drive failures out of the 64, WD Red NAS disks. The most interesting was one that kind of cooked off. The log indicated that it had gotten to over 130 °C before it stopped responding. Apparently, it caused the two drives adjacent to it to also fail, but with bad sectors instead of catastrophically. The system used the hot spare to replace the failed drive and everything continued running.

A drive that went stone dead immediately would fail gracefully and be offlined, it was the "hey I'm here, whoops I'm gone, repeat" that would do greater damage.

I hate when a drive is intermittent or just gets slow for no reason that shows up in SMART data.

 

[HoneyBadger]

The most interesting was one that kind of cooked off. The log indicated that it had gotten to over 130 °C before it stopped responding.

I don't think that's what we generally want when we say "hot spare" ;)

I hate when a drive is intermittent or just gets slow for no reason that shows up in SMART data.

And generally speaking that's the kind of bizarre and intermittently buggy behavior that resolved itself entirely with using SAS drives.

I'm generally the type to advocate for the overbuilt but ultimately safer solution (hence the signature line) unless the risk of data loss is acceptable. For most large "home builds" it tends to be users amassing a large volume of "questionably ethically sourced media files" and the chance of an edge-case causing total failure is acceptable, but I'm used to the enterprise world where "losing your data" usually correlates with "losing your job"

 

[NaCl]

I don't think that's what we generally want when we say "hot spare" ;)


And generally speaking that's the kind of bizarre and intermittently buggy behavior that resolved itself entirely with using SAS drives.

I'm generally the type to advocate for the overbuilt but ultimately safer solution (hence the signature line) unless the risk of data loss is acceptable. For most large "home builds" it tends to be users amassing a large volume of "questionably ethically sourced media files" and the chance of an edge-case causing total failure is acceptable, but I'm used to the enterprise world where "losing your data" usually correlates with "losing your job"

Yet another reason to invest in a tape backup solution of some lto generation. LTO-6 is on the edge of the likely budget of a home user, 5 is almost cheap enough to be disposable, 4 is nigh free. My media collection represents a very large (coming on 1k I'd guess) # hours of manual ripping of my optical masters, transcoding, and curation. It would be a devastating punch to the groin were all that effort to go "poof!"

The piece of mind, for me, has been totally worth it.

Sent from my Pixel 2 XL using Tapatalk

 

[Arwen]

A variety of SAS1 expanders. The issue may be resolved as of SAS2 but I'm erring on the side of caution.
...

Yes, there were problems with SAS 1 expanders that have SATA disks. This is clearly resolved with SAS 2 and later, (SAS IV / 4 is being released very soon, if not
already). So that advice is basically out of date.

Please note that some of the early problems were SATA 1 disks that used 1.5Gbps. SAS standards no longer support, (or never did), SATA 1 backward compatibility.
There were a few SAS 2 controller chips that did support SATA 1 disk speeds. Even some that did in earlier firmware that later firmware dropped.

 

[Arwen]

As an addendum to what @Arwen said above, some external drive cages use SATA port multiplication. These are bad for ZFS. Don't use them.

Others actually implement some manner of RAID within themselves and use DIP switches or similar jumpers to present the drives as a single volume. These are absolutely abysmal for ZFS. Don't use them.
...

One way to check for these, is the amount of eSATA connections. If there is only 1 and there are more than 1 SATA disk slots, then they have one of the above. They are to be avoided like the plague for normal pool usage as they almost certainly hide SMART and disk block sparing features.

 

[Arwen]

Yet another reason to invest in a tape backup solution of some lto generation. LTO-6 is on the edge of the likely budget of a home user, 5 is almost cheap enough to be disposable, 4 is nigh free. My media collection represents a very large (coming on 1k I'd guess) # hours of manual ripping of my optical masters, transcoding, and curation. It would be a devastating punch to the groin were all that effort to go "poof!"

The piece of mind, for me, has been totally worth it.

In some cases, simply using a (very) large removable disk(s) can work well for backups. My NAS has only 8TB of usable storage, (4 x 4TB in RAID-Z2), and I use an 8TB disk as one of my backups.

That said, this is a more modern backup scheme for me. In the past, I had multiple tape drives and media;

• DLT-2000XT, DLT-1, DLT-7000
• SLR5, MLR1
• EXB-8200, EXB-8500, EXB-8505 XL

But, when I moved 5 years back, I got rid of all that old stuff, including all my parallel SCSI equipment.