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SCSI2SD in DEC SBB?

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dtih

Experienced Member
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Sep 1, 2017
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Today I started up my DEC Alpha 1000A and some of the SBB Bricks were dead. Is it possible to put a SCSI2SD in a SBB to replace an existing hard drive?
 
dtih said:
Today I started up my DEC Alpha 1000A and some of the SBB Bricks were dead. Is it possible to put a SCSI2SD in a SBB to replace an existing hard drive?
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The dark blue StorageWorks caddies convert the backplane to SCA SCSI, normally LVD/wide. You might need a SCA to normal (68-pin + molex power) drive adapter, depending on what the connectors the SCSI2SD has. There is a switchpack on the SCA interposer flex ribbon cable, but I've never needed to change the switch settings when changing drive models. It is possible to have a bad interposer board where even a good drive won't be properly recognized. I've seen situations where the drive appeared totally dead, had its activity LED stuck on, or actually hung the SCSI bus. So make sure the problem is actually the drive and not the caddy.
 
The SCSI2HD and it's successor the ZuluSCSI are 50-pin SCSI-1/2 devices. I imagine you can put one in a DEC SCSI brick, but you might need to make a 3.5" to 5.25" conversion mount. It also tops out at about 9.5Mb/s so it won't compete with most LVD disks (blue canister). The earlier tan(?) canisters were SCSI 1/2 so would be more comparable.
 
The caddies I have are green in color, they are a bitch to open. I have to go back and look at the hardware configuration of this system, there are a number of, what look like, external SCSI connectors on the back of the machine. That might be a better place to attach a SCSI2SD....
 
dtih said:
The caddies I have are green in color, they are a bitch to open. I have to go back and look at the hardware configuration of this system, there are a number of, what look like, external SCSI connectors on the back of the machine. That might be a better place to attach a SCSI2SD....
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Yeah. I've replaced many a drive in those bricks. You have to be very careful pressing the tabs or else you snap them off. At some point, sometimes, the plastic has gotten brittle and nothing you will do will stop it. But once that's done swapping a good drive in is a piece of cake. It's been at least 10 years since the last one I've done. I had an RA7000 storage system with 24 (?) slots, though some were for the redundant P/S. I gave it and the AS1200's that also had the brick containers away when I moved to Texas at the end of 2017. Now all I've got are a couple Compaq 4200/4300 shelves with the drive sleds. Anyway, I don't remember the internal configuration of the bricks. Though the SCSI2HD card is light enough to just hang off the short ribbon cable inside. It's not going to flop around much and not likely to cause damage if it does since there are no heads to crash.
 
dtih said:
The caddies I have are green in color, they are a bitch to open. I have to go back and look at the hardware configuration of this system, there are a number of, what look like, external SCSI connectors on the back of the machine. That might be a better place to attach a SCSI2SD....
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IIRC, there are 4 pop catches between the top and bottom of the clamshell, and another two on the sides where the front panel attaches. One or more of these may be covered with "warranty void if removed" stickers. Don't unscrew the 4 drive screws first or you'll have a drive flopping around when you open the clamshell.

Reassembly goes pretty much the same way, but make sure the interposer-to-backplane connector is trapped in the right position before snapping the clamshell closed.

On my DS20 (recently donated to the LSSM) I had installed the "split bus" option back in the late 1990's shortly after the system was purchased, giving me the top 4 slots on one cable and the bottom 3 on another. These went to a 3X-KZPEA-DB Adaptec 39160 LVD SCSI controller, so there were lots of available LUNs for the external connectors.

If the SCSI2SD is narrow and/or single-ended only, you don't want to intermix it on the same bus as wide / LVD drives. If you don't have a split bus but do have the KZPEA, you can just use the other bus for external devices.

There's also a narrow/single-ended controller based on a Qlogic ISP1020 (I don't recall the DEC part number) which might be another possibility.
 
I've got 2 Qlogic ISP10x0 controllers showing up, the DEC part is KZPBA_CA. The way to go is to use these with some kind of SCSI to SD device.
 
ZuluSCSI boards can emulate up to 6 drives, of course - I think SCSI2SD are the same - and yes, limited transfer rate - but near zero seek time makes up a lot of performance if not doing huge file transfers...

Use the industrial or high endurance SD cards if possible...

Robin
 
dtih said:
I guess the question I'm trying to answer is, are there any emulators of the higher end SCSI drives?
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i think all the really good stuff is still prohibitively expensive, and i don't think it's economical yet for hobbyists to produce a board that can emulate a scsi drive with a sata ssd

i believe there are some industrial grade scsi ssd replacement type deals (names are escaping me right now) but they never list prices and i can't imagine they're even remotely affordable
 
dtih said:
I guess the question I'm trying to answer is, are there any emulators of the higher end SCSI drives?
Click to expand...

hush said:
i think all the really good stuff is still prohibitively expensive, and i don't think it's economical yet for hobbyists to produce a board that can emulate a scsi drive with a sata ssd

i believe there are some industrial grade scsi ssd replacement type deals (names are escaping me right now) but they never list prices and i can't imagine they're even remotely affordable
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Once upon a time there was a company named ACARD. And ACARD produced a magical device called a SCSI bridge. They bridged SCSI to IDE, to SATA and had specific cards for Optical (that is CD/DVD drives) and regular disk storage.


Sometime around 2017 something happened and ACARD stopped producing these cards (most were like the interposer cards used now for SCA-80 to 68/50 pin SCSI). They pop up on Ebay occasionally as NOS but the asking price is always in the $1000 range. When ACARD was producing them, they typically were around $80 each - each card interfaced one device. Quite often you will see the ACARD 7732 listing for anywhere between $175 and infinity. Don't be fooled. it's only good for interfacing CD/DVD or other optical drives. From what I can see on the web, people have tried hard drives and it won't work. There are parts of the SCSI protocol it apparently ignores ( or something like that, I'm not a SCSI engineer so I don't know the details).

ACARD stopped updating it's web site in relation to these cards around 2017 so even though the site works, I don't know if the company is alive currently.

ACARD SCSI Bridge page: http://www.acard.com/index.files/Page385.htm

I don't know what happened to them. From the pictures it looks like they use a custom FGPA or ASIC. Maybe it went out of production and they couldn't find a suitable replacement. You would think it would be a viable product for someone, but if you Google SCSI-SATA bridge, ACARD is the only company that comes up except for a few oddball ones and they are mostly old (2012 era).
 
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The KZPBA looks an awful lot like an ADAPTEC controller. I use an ADAPTEC controller in a PC to communicate with a SCSI2SD I use for PDP11s. The ADAPTEC has a 50 pin connector for old style SCSI and works just fine. The KZPBA manual also talks about a 50 pin connector, I wonder what happens if I connect a SCSI2SD to it in the Alpha 1000A?
 
I would expect it to work. Take time to read and understand the documentation. I've used the SCSI2HD for a number of years. I used them in a MV3100 M95 (in fact it's the only storage in it) and on Alphaserver DS10's with no issues. It was the V6 SCSI2HD. Now I use ZuluSCSI 2040's in both. I know several people that have used SCSI2HD with the Emulex UC07 in PDP-11 and VAX QBus based systems.

Do you have a SCSI2HD on hand? If so, then use that. If not, then look into the ZuluSCSI which is a cross between a SCSI2HD and the BlueSCSI disk emulator cards. The ZuluSCSI is slightly cheaper and has an easier disk interface to work with and is slightly faster. http://zuluscsi.com/

I just bought 2 ZuluSCSI 2040's to put in a new MV3100 I got. Ordered on Sunday, delivered to DFW Texas area on Tuesday. If you're not i the USA then there are other vendors. http://zuluscsi.com/wheretobuy/
 
reinhardtjh said:
Once upon a time there was a company named ACARD. And ACARD produced a magical device called a SCSI bridge. They bridged SCSI to IDE, to SATA and had specific cards for Optical (that is CD/DVD drives) and regular disk storage.


Sometime around 2017 something happened and ACARD stopped producing these cards (most were like the interposer cards used now for SCA-80 to 68/50 pin SCSI). They pop up on Ebay occasionally as NOS but the asking price is always in the $1000 range. When ACARD was producing them, they typically were around $80 each - each card interfaced one device. Quite often you will see the ACARD 7732 listing for anywhere between $175 and infinity. Don't be fooled. it's only good for interfacing CD/DVD or other optical drives. From what I can see on the web, people have tried hard drives and it won't work. There are parts of the SCSI protocol it apparently ignores ( or something like that, I'm not a SCSI engineer so I don't know the details).

ACARD stopped updating it's web site in relation to these cards around 2017 so even though the site works, I don't know if the company is alive currently.

ACARD SCSI Bridge page: http://www.acard.com/index.files/Page385.htm

I don't know what happened to them. From the pictures it looks like they use a custom FGPA or ASIC. Maybe it went out of production and they couldn't find a suitable replacement. You would think it would be a viable product for someone, but if you Google SCSI-SATA bridge, ACARD is the only company that comes up except for a few oddball ones and they are mostly old (2012 era).
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Yes, I've noticed the nutty prices on eBay. Fortunately I purchased a couple of AEC7726 bridge boards in the late 00s. I guess that makes me a thousandaire?
 
Thanks for that info, I have used the SCSI2SD in MV3100 and Alpha attached to the internal generic DEC SCSI interface. In QBUS PDP11's I've attached it to all kinds of cards with success. Its time to take advantage of progress!
 
I purchased a Zuluscsi board for the Alpha 1000a. Not sure where to hook it, the two KZPBA SCSI controllers talk to the drives in the StorageWorks cabinet, one for the top 4 drives and the other the bottom 4 drives. I'll try this, empty the top 4 drives (where the dead ones are) and attach the ZuluScsi to the controller for that portion of the StorageWorks. I read where that attaching a narrow SE device will cause all drives to be treated as SE narrow.
 
I believe that's the HBA I have in my DS10's. Internally it has a 68-pin and a 50-pin connector on separate SCSI buses. Externally it has a single 68-pin connector. You can use either the internal and not the external or you can use the External and not the internal connectors. Since you have a Storageworks shelf, I assume you are using the external connector only. The only issue I see is that the external SCSI bus is 16-bit and the ZuluSCSI is 8-bit. The Storageworks shelf can handle both, but I'm not sure where there conversion is done - in the shelf's SCSI interface or in the SSB brick. Unless you mean to connect the ZuluSCSI directly to a cable from the KZPBA. Then you just need a 68-pin to 50-pin adapter. It needs to handle the termination of the extra 8 lines.

The adapters I see are intended for internal cable connections. But one of these might work with an external cable.

www.ebay.com

SCSI 68pin to IDE 50pin Male to Male Female to Female Adapter HPDB68pin Converte | eBay

SCSI 68pin DB type. Pitch: SCSI 68pin 1.27mm. IDE 50pin 2.54mm. IDE 50pin converter,NOT compatible with IDE 40pin/44pin interface. 1 piece converter, upon your choice.
www.ebay.com
www.ebay.com

SCSI-3 HPDB68 Male to IDC50 Male Internal SCSI Adapter, CablesOnline AD-S25 | eBay

SCSI-3 HPDB68 Male to IDC50 Male Internal SCSI Adapter. Connector 2: HPDB68 SCSI-3 MaleCablesOnline Part Number: AD-S25. Connects a SCSI-3 Internal Hard Drive with Micro 68-Pin Female Connector to an internal IDC-50 Pin Female Ribbon cable.
www.ebay.com

Maybe not, but that would be the style you need - 68-pin female to 50-pin male.
 
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I've had this alpha for a couple of years, how do I open it up? It was not obvious to me, its heavy and doesn't lend itself to be flipped over and around lightly. I want to remove some of the extra PCI cards that were controlling an external RAID. Also, I would like to ID and replace the Dallas TOY IC.
 
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