New to Scsi drives etc!

[belfasteddie]

Hi, I hope you don't mind me joining this Tek site, I'm looking for some info re Scsi drives etc.
I have just pulled apart a Compaq 3000/450. I salvaged the Scsi drives, 15 in total, plus the dual cpus and the Ram.
I have just purchased a Microtech 440x brd which has two Ide and two 80 pin scsi connectors.
My questions are:
1: Do I just plug the drives in with a scsi ribbon, or do I need a scsi controller card?
2: There is 12 Compaq normal size scsi + three Fujitsu, which appear to be about twice the height of the Compaq. Why?
3: One of the drives has Win2000 on it , will I be able to use it as a Boot disk?
4: Pin selection: I wish to use the drives as single drives, how which pins do I jumper?
Any help would be gratefully appreciated.
Eddie.

 

[wahnula]

Here's a quick read:

http://www.pcguide.com/ref/hdd/if/scsi/index.htm

You need to be familiar with the SCSI bus' quirks. It is a very robust bus but has unique requirements, like numbering the devices and terminating the chain. It's been a long time since I've dealt with SCSI but the basic principles are easy to understand and get used to.

If there is a SCSI jack on the M/B then you can assume there is an integrated SCSI controller, probably for the boot drive. If it was previously used with the MB in your possession, the Win2K drive MIGHT work.

Check out the SCSI BIOS during boot to see if the drives are being seen. Best of luck!

Tony

Users helping Users...

 

[edfair]

Use a google search to find the specifications on the drives by manufacturer and drive model number. That generally will tell you the capacity and the jumpering.


The Fugis are probably half height drives (1/2 the height of the original 5 1/4 hard drives (3 3/4) while the Compaqs are probably badged 1" drives from an OEM supplier.

It is possible that the Compaqs were part of RAID arrays and mounted on sleds (mounting plates) allowing for hot swap replacements in case one failed. That would be the general arrangement for a server handling a lot of data.


Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[goombawaho]

You have to have a SCSI controller on one end of the chain (with termination ENABLED) and all the hard drives have to be connected with the last one having termination enabled on the drive.

http://www.seagate.com/support/kb/disc/termination.html

Each drive must have a unique SCSI ID set manually if they are drives with jumpers on them. It's automatic if the drives fit into a hot swap enclosure/server. You may not be able to use hot swap drives in a non-hot swap environment, because it's not the same interface as a regular scsi cable has.

Take a look here for the type of connection you have.

http://www.adaptec.com/tools/selectors/cables.html

Older drives used the 50 pin (HD50) connectors while newer ones use the HD68 or V68 connection.

Look up the SCSI ID setting for each hard drive on the manufacturer's web site if it's not shown on the outside of the drive. I know a lot of scsi cards when posting will show you the devices and their scsi ids. This is one way to check your work.

 

[belfasteddie]

Hi Guys, many thanks for your replies.
Wahnula,The Win2k drive was part of the Compaq setup.It was setup using Raid( don't know what version) My question is if it was raid can I still use it as a stand alone drive, will it still boot? The Motherboard isn't the Compaq.

 

[belfasteddie]

Guys, I have checked and found out that my drives use active termination. I have read quite a few guides in the last couple of hours and nowhere does it tell you HOW to do it.
Do I use one of the jumpers?

 

[edfair]

Active termination means that there is something active, not just a resistor. Doesn't mean that there is termination on each drive, just that whatever termination used should be active, although it might be on the end drive. Active helps the pull up, pull down work faster.
One of the jumpers on the drive should enable termination. Only the end drive should have been terminated, the rest unterminated. Or there may have been an active termination device on the cable. Generally a small black device 1/4" by 2 1/2" by maybe 1" plugged into a header or built onto the cable.

So you understand the issue: When you have a single ended source feeding a resistor the voltage at the resistor doesn't instantaneously rise to the same voltage as the source's supply. It rises like the first quarter of a sine wave. Somewhat like a bucket fills up through a hose. An active terminator recognizes the voltage change and connects an internal supply to pull up the voltage faster. Like a switch turning on another hose when needed to fill the bucket faster. All this to get the levels changed fast enough so data gets transferred correctly.


Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[belfasteddie]

Ok Thankyou.

 

[wahnula]

if it was raid can I still use it as a stand alone drive

Only if it was originally part of a RAID 1 (mirrored) array. Any other RAID level will not work with a single member drive.

Tony

Users helping Users...

 

[edfair]

Tony, I think he meant as a stand alone boot disk.

I would suspect that the drive marked 2K was a stand-alone to start with and not part of a raid array. And it may try to boot by itself but probably fail because the hardware has changed. You plug it in and see what happens. The very worst is an error message, it hangs up, and you have to load the operating system.



Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[belfasteddie]

The Win2k was the O/S on the compaq server. It ran for about one hour and then failed . I replaced the drive with a spare but the machine then asked me to cross some files as it couldn't find them . I was then lost so pulled the machine apart, kept what I wanted and dumped the rest.
I am now at the point where I will marry the M/b and the Compaq drives etc. I am only doing this to run Beos 4.5 and 5 and hopefully Win2k.I run Zeta 1.5 on one of my desktops but cannot run Beos on it as it is too modern.
By the way , I appreciate all the help. I am 62 yrs of age and have 25 yrs plus in computers but have never used scsi , thats why I need the help.

 

[goombawaho]

You should tell us about the drives (brand model) so we can recommend a SCSI controller. You probably don't have what you need to connect the drives to the motherboard at this point.

Never heard you say that you had a SCSI controller.

 

[edfair]

And in case the drive info you can find is not sufficient to identify what you have, tell us what kind of connector is on the drive.

The variety of SCSI interfaces can be a puzzle to match up.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[belfasteddie]

Hi Guys. I have D/l the PDf file of the M/B manual. The M/B is a Supermicro P6DBS and has an Integrated onboard Adaptec 7895 multichannel UW.(2 of). The Hard drives are Compaq 9.1 gig p/n313706-b21 and Fujitsu p/n ca01407-b760.
The Compaqs have a diagram of the jumper pins and the following:id3,id2,id1,id0,key,start cmd,na,sp sync,led,write prot,del start,force se,dis ti sy,dis par,dis un a,dis f/w neg. The fujis are totally enclosed and only have the cable connector showing.
Am I correct in thinking the scsis don't need a power connector as in an Ide?
The connector is about 2 1/2 inches long?

 

[edfair]

You are dealing with hot swap drives that get their power through the 80 pin connector. The power on those I've dealt with came from a 4 pin drive connetor onto the drive cage where the power and signal are combined on the cage electronics. Try a google search for "SCA SCSI" for the details.

Most consumer SCSI have 50 pin IDH connectors or 68pin HD "D" shell connectors and the same 4 pin power as an IDE.

I don't know what your connection issues will be. I haven't done any swapping around of drives with this connector.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[belfasteddie]

Edfair, thankyou you just turned the light on.

 

[goombawaho]

The problem is going to be (and I've never tried this) if you can pull of the 80 pin interface to reveal a regular 4 pin molex power supply connection and a SCSI connection to which you can connect your motherboard.

You're sort of like playing Dr. Frankenstein here trying to use those drives in a non-hot swap environment.

 

[goombawaho]

I'm thinking the answer is no. Look at this picture

http://en.wikipedia.org/wiki/Image:SCSIHardDriveConnectors.jpg

 

[edfair]

Once again google is your friend. Try "sca 68 pin" to see converters. Or look for the same thing on ebay.

There are still issues however. The interfaces may still be incompatable. Like single ended requiring a terminator, or differential not requiring one.

But since the Compaqs had a terminator disable jumper set I suspect they are single ended.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[goombawaho]

Here's the real bottom line for me - why bother. I mean, you've got to do a bunch of work and maybe buy and adapter and/or a controller card just to use some old 9GB drives that may fail any week.

I wouldn't bother unless it's purely for fun. And don't spend too much money "chasing the dream". Taking off advice giver hat now.