# Picking the right SCSI card: LVD



## dvl@ (Mar 21, 2014)

I'm bad at knowing the right SCSI card.  I'm looking for help.

I posted details and photos at https://plus.google.com/106386350930626 ... PFoCYtSDdd

The tape library in question is LVD/SE with 68 pin connectors.  I have the right cables.  I just need a card.  Any card will do.  I just don't know what to search for on eBay.

The server it's going into has PCI slots (http://www.supermicro.com/aplus/motherb ... /h8sgl.cfm).

I think this is an appropriate card: http://www.ebay.com/itm/SUN-348-0036690 ... 3a7fa3e369

Anyone with more knowledge?


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## SirDice (Mar 21, 2014)

I can't comment on FreeBSD's compatibility with the card but SCSI-wise it looks appropriate. The server also has PCIe x8 and x4 slots, it may be worthwhile to look for a similar card for those slots. They should be faster so you'll get better I/O throughput. But it'll be overkill if the tape library can't provide the bandwidth. Or if you don't care how long things take


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## dvl@ (Mar 21, 2014)

The tape library can do 11MB/s max.


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## dvl@ (Mar 21, 2014)

But you raise a very good point. Perhaps my question should be: what SCSI card is known to work with FreeBSD given the requirements?

* PCI slot
* 68 pin
* LVD/SE


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## dvl@ (Mar 21, 2014)

Given the devices is LVD/SE, I take it that either an LVD or an SE card will suffice.

If I use an SE card, will that limit the transfer rate to 5MB/s?

If so, I definitely want an LVD card, so we can do saturate the tape, which can write at 11MB/s.


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## dvl@ (Mar 21, 2014)

I think I have a lead on a Symbios 22801, which seems to be supported by FreeBSD.


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## dvl@ (Mar 21, 2014)

And the LSIU80LVD may be useful too. I found an LVD one: http://www.ebay.com/itm/LSI-Logic-Dual- ... fresh=true


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## Terry_Kennedy (Mar 23, 2014)

dvl@ said:
			
		

> I'm bad at knowing the right SCSI card.  I'm looking for help.
> 
> The tape library in question is LVD/SE with 68 pin connectors.  I have the right cables.  I just need a card.  Any card will do.  I just don't know what to search for on eBay.
> 
> ...


That card is a HVD (original differential, now called High Voltage Differential to distinguish it from LVD). It is incompatible with anything except HVD devices.

Your best bet would be an Adaptec 29160 (single-channel) or 39160 (dual-channel) card. The 29160 has the traditional "big" 68-pin connector, while the 39160 uses the smaller VHDCI connectors. Electrically they're compatible, but they don't interchange physically. Also, the "big" 68-pin connector can use either thumbscrews or clip locks, and you need the right kind. Some devices have dual-mode retention, but from your pic your drive uses thumbscrews only.


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## dvl@ (Mar 23, 2014)

Right you are.  It's a SCSI-diff.  I'll search for those cards.


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## dvl@ (Mar 23, 2014)

Terry_Kennedy said:
			
		

> Your best bet would be an Adaptec 29160 (single-channel) or 39160 (dual-channel) card. The 29160 has the traditional "big" 68-pin connector, while the 39160 uses the smaller VHDCI connectors. Electrically they're compatible, but they don't interchange physically. Also, the "big" 68-pin connector can use either thumbscrews or clip locks, and you need the right kind. Some devices have dual-mode retention, but from your pic your drive uses thumbscrews only.



The Adaptec 39160 is appropriate because the tape library has VHDCI connectors.  However, it seems both cards are PCI-X only, and the board has only PCI-E or PCI slots available.

I appreciate the help.


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## Terry_Kennedy (Mar 23, 2014)

dvl@ said:
			
		

> The Adaptec 39160 is appropriate because the tape library has VHDCI connectors.  However, it seems both cards are PCI-X only, and the board has only PCI-E or PCI slots available.


From the Adaptec manual: _"Although the Adaptec SCSI Card 39160 is a 64-bit PCI card, it also works in a 32-bit PCI slot. When installed in a 32-bit PCI slot, the card automatically runs in the slower 32-bit mode."_

In fact, that seems to be one of the cited sources for the Wikipedia PCI article, which says

_"*Mixing of 32-bit and 64-bit PCI cards in different width slots*

Most 32-bit PCI cards will function properly in 64-bit PCI-X slots, but the bus speed will be limited to the clock frequency of the slowest card, an inherent limitation of PCI's shared bus topology. For example, when a PCI 2.3, 66-MHz peripheral is installed into a PCI-X bus capable of 133 MHz, the entire bus backplane will be limited to 66 MHz. To get around this limitation, many motherboards have multiple PCI/PCI-X buses, with one bus intended for use with high-speed PCI-X peripherals, and the other bus intended for general-purpose peripherals.

Many 64-bit PCI-X cards are designed to work in 32-bit mode if inserted in shorter 32-bit connectors, with some loss of speed.[19][20] An example of this is the Adaptec 29160 64-bit SCSI interface card.[21] However, some 64-bit PCI-X cards do not work in standard 32-bit PCI slots.[22][unreliable source?]

Installing a 64-bit PCI-X card in a 32-bit slot will leave the 64-bit portion of the card edge connector not connected and overhanging. This requires that there be no motherboard components positioned so as to mechanically obstruct the overhanging portion of the card edge connector."_

You probably want to avoid parallel (classic) SCI on PCIe - the adapters are horribly expensive, since PCIe and SAS arrived at roughly the same time and there are far fewer parallel SCSI adapters available for PCIe.


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## dvl@ (Mar 23, 2014)

Terry_Kennedy said:
			
		

> You probably want to avoid parallel (classic) SCI on PCIe - the adapters are horribly expensive, since PCIe and SAS arrived at roughly the same time and there are far fewer parallel SCSI adapters available for PCIe.



Looking at the m/b, it looks to be obstructing such a plan.  There is a photo of the available slots here: https://plus.google.com/106386350930626 ... PFoCYtSDdd


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## dvl@ (Mar 24, 2014)

It seems there are a number of Symbios 22801 cards on ebay: http://www.ebay.com/sch/i.html?_odkw=sy ... I&_sacat=0

comments on that model?


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## Terry_Kennedy (Mar 24, 2014)

dvl@ said:
			
		

> It seems there are a number of Symbios 22801 cards on ebay: http://www.ebay.com/sch/i.html?_odkw=sy ... I&_sacat=0
> 
> comments on that model?


That is a classic wide SCSI adapter (single-ended only, no LVD). It should work as long as it and your drive/library are the only things on the bus - the drive will fall back to SE operation. You'll get a lower transfer rate - not a problem for a DLT8000 drive, but may limit throughput on a SDLT drive.


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## dvl@ (Mar 24, 2014)

Terry_Kennedy said:
			
		

> dvl@ said:
> 
> 
> 
> ...



That may be an issue.  I already have an LSI SAS 2008 with 8 SATA drives on this sytem.  I wouldn't want to slow down the storage.  Or I wonder if they are already being slowed down?

The full dmesg output (from http://dan.langille.org/2013/08/18/knew/) includes:


```
mps0: <LSI SAS2008> port 0xb000-0xb0ff mem 0xfdc3c000-0xfdc3ffff,0xfdc40000-0xfdc7ffff irq 44 at device 0.0 on pci1
mps0: Firmware: 15.00.00.00, Driver: 14.00.00.01-fbsd
mps0: IOCCapabilities: 1285c<ScsiTaskFull,DiagTrace,SnapBuf,EEDP,TransRetry,EventReplay,HostDisc>
...

sym0: <875> port 0xe000-0xe0ff mem 0xfebeec00-0xfebeecff,0xfebef000-0xfebeffff irq 21 at device 3.0 on pci4
sym0: Symbios NVRAM, ID 7, Fast-20, SE, parity checking
sym0: open drain IRQ line driver, using on-chip SRAM
sym0: using LOAD/STORE-based firmware.
```


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## dvl@ (Mar 24, 2014)

Terry: I do appreciate your advice in this area.  Another search and I find this LVD card: http://www.ebay.com/itm/Symbios-SYM2280 ... 3cd8653703

But I'm not sure of the connector.  It appears to be non-VHDCI

Perhaps I need to just buy a VHDCI converter


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## jalla (Mar 24, 2014)

dvl@ said:
			
		

> Terry: I do appreciate your advice in this area.  Another search and I find this LVD card: http://www.ebay.com/itm/Symbios-SYM2280 ... 3cd8653703
> 
> But I'm not sure of the connector.  It appears to be non-VHDCI
> 
> Perhaps I need to just buy a VHDCI converter



You just need to buy the right cable. Standard scsicables come with any combination of microD-68 (SCSI-3) and VHDCI (SCSI-5) connectors.


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## dvl@ (Mar 24, 2014)

Jalla: good point.  The right cable.

A Linux friend mentioned the SYM8951U, which appears to be supported by the FreeBSD sym(4) driver.  They are PCI, LVD/SE, and have a VHDCI connection

e.g http://www.ebay.com/sch/i.html?_trksid= ... &_from=R40

Anyone have experience with those cards?  Anyone agree with my conclusion that they are supported?


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