If you have more than one SCSI storage device on a Windows Server 2003 system, you might develop a problem with
Plug and Play, Microsoft's system for finding hardware on the system and matching it up with the appropriate device drivers and other necessary resources.
Plug and Play is a fairly sophisticated chunk of software that, for example, selects from among several options for finding the correct device driver if it can't find the driver for a specific device.
With more than one SCSI device, you might encounter the following symptom: The computer will freeze and you get a Stop 0x000000CA error message. The Microsoft documentation will tell you only that the message means you have a fatal error in Plug and Play. . .which is not terribly helpful.
The key to Plug and Play's ability to match drivers and hardware is the Plug and Play ID, a number assigned to each device by Microsoft and the hardware manufacturer. The ID tells Plug and Play what the device is. Theoretically, different kinds of devices should not have the same Plug and Play ID. But in this case, the theory has broken down; the SCSI storage devices are reporting the same Plug and Play ID. The result is a conflict that at best disables the SCSI devices and at worst crashes the system.
Microsoft offers a hotfix to resolve the problem. (As always, Microsoft recommends only installing the hotfix if you are having this specific problem.)
Rick Cook has been writing about mass storage since the days when the term meant an 80K floppy disk. The computers he learned on used ferrite cores and magnetic drums. For the last 20 years he has been a freelance writer specializing in issues related to storage and storage management.
More information from SearchWinSystems.com
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- Topics: SCSI
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