Subject: Re: Please help (microcode)
Date: Mon, 20 Oct 1997 23:12:11 -0500
On 9 Oct 97 at 15:35, Arpool Pace wrote:
> Would you know of any list of vendors, other than Wang,
> that offer scsi drives for VS systems?
A number of third party vendors offer SCSI drives for the VS, with Wang firmware. It doesn't make much sense, though, because Wang has become very competitive in the area of SCSI disk drives, and if you have the CPU under maintenance the monthly cost of maintaining the new SCSI disk drives you buy from Wang is, get this, ZERO! Compare that to getting a drive from a third party company and having to ship it back when it gives you trouble. That's like getting mail-in medical treatment. "We'll sell you a leg, cheap. If anything goes wrong with it during the warranty period, just ship it back to us and we'll fix or replace it in, oh, maybe a week."
> Or would you know where I might pick up Wang microcode so
> that I may set up the scsi drive of my choice? Thanks for
> the help,
That's a no-no, if you mean the disk drive firmware. It's also highly unauthorized to use patched SCSI IOC microcode that allows non-Wang firmware drives to mount at IPL without giving an error message and requiring an operator acknowledgement.
Here's the full story: There are basically two types of SCSI disk drive. One type is rated for commercial/industrial use, has a very high Mean Time Between Failure (MTBF) rating, has a large amount of on-board cache, and more fully and faithfully implements the SCSI specs for successful operation with serious minicomputers and mainframes. The other type is for consumer use, may or may not have a high MTBF, is light on cache, and may cut corners on the SCSI spec or just not be fully tested and debugged as to firmware. When you look at SCSI disk prices in the back pages of Computer Shopper you will see a large price difference between these two types of SCSI drive and you will generally notice that the more expensive ones, sometimes referred to as "commercial" grade, have 256K and 512K on-board cache memory.
You need commercial grade SCSI drives for your VS.
Beyond that, there is something else. When a computer vendor such as Wang or IBM or HP or DEC sells a disk drive to an installed base of tens of thousands of customers, they have to make very sure the device is solid. If it isn't, they have to deal with thousands of trouble calls, many under warranty and most under fixed-price service contracts. That translates into a lot of headaches and a lot of cost.
As a result, the major vendors, particularly of large systems as opposed to consumer systems, are very conservative in how they select and qualify critical equipment such as disk drives. They generally qualify SCSI disk drives by an exhaustive process that tests not only their reliability under commercial/industrial conditions of use, but they also carefully examine and verify that the complex SCSI protocol is fully and correctly supported by the drive's on-board electronics. If it isn't, the drive may not function correctly under error conditions, or may not handle status and error reporting correctly, leading to failure to detect drive malfunction or misinterpretation of malfunctions.
Wang certifies drives for use with VS systems only after putting them through an exhaustive process that few if any consumer disk drives ever have to endure. They handle the firmware problem by providing their own firmware for certified drives.
At one time all this resulted in much higher prices for Wang drives than for competing, less-qualified and sometimes unknown drives. Now, though, Wang's prices are only slightly higher than competing bargain-basement commercial drives that carry Wang certification. I wouldn't even consider a non-certified drive as that would invite problems that aren't worth having.
Really... I used to think the business of Wang-certified drives was a lot of hokum until I read about what's behind the certification, and caught on to the difference between commercial and consumer disk drives. Then it all became perfectly clear.
I've seen places that saved a little bit on a 4gb drive, then had to FedEx the drive back to the distributor when it failed and wait for a replacement (which sometimes will no longer be available), with the system lacking a 4gb drive meanwhile. Had it been a Wang drive it would have been replaced on the spot, the same day, at no charge (under maintenance contract, of course, but $0.00 per month for the SCSI drive if bought from Wang).
> Oh, and I would like to subcribe too! 
[unrelated material omitted]
Regards,
Thomas Junker