Media Changers

This section defines requirements for media changers.

CD Changers

This section provides requirements for CD changers.

There is no requirement or recommendation for providing a CD changer with a server system, but if present or designed to be compatible with Windows NT 5.0, it must comply with these requirements.

CD changer for seven or fewer discs meets MMC-2 standard

Recommended

If an ATAPI-compatible CD changer is present that supports seven discs or less, the device should comply with the MMC-2 standard.

Tape and Optical Disk Changers

This section provides requirements for tape and optical disk changers. There is no requirement or recommendation for providing a tape or optical disk changer, but if a device is present or is designed to be compatible with Windows NT 5.0, it must meet the requirements defined in this section.

This includes changers that support the following drive/media types:

• 3.5-inch, 5.25-inch, and 12-inch magneto-optical or phase-change drives and media
  
  
• All magnetic tape drives and media

It does not include changers that support CD-ROM, CD-R, CD-Rewritable, or DVD drive/media types.

SCSI changer and drive support auto-configuration

Required

To meet requirements for auto-configuration of changers and their associated drives, the following changer requirements and configuration restrictions are defined:

• For changers where autoconfiguration under Windows NT Media Services (NTMS) control is a targeted feature, all changer tape or optical disk drives must be connected to the same SCSI bus as the changer.

Changer systems that are not configured this way will not be autoconfigurable under NTMS in Windows NT 5.0 and must provide documentation that describes the appropriate manual configuration process for use with NTMS. Examples of proper documentation are available in Appendix A of NTMS Programmers Guide, at http://www.highground.com/developer/documents/ntmsdocu.htm.

• The changer’s Read Element Status–Data Transfer Element Descriptor must support the reporting of the SCSI Bus Address and LUN of each drive in the library unit.
  
  
• If drive cleaning is required and can be automated, a specific slot that is accessible by way of a Move Medium command must be designated in the Operator’s Guide.
  
  
• The changer must be able to report if a bar-code reader is installed in the unit.
  
  
• The changer must be able to report on the current of (magazine) slots and drives by using the Read Element Status command.

SCSI tape and optical disk changers support SCSI commands

Required

The following commands or features must be supported by the changer:

• Initialize Element Status (with/without bar-code reading)
  
  
• Mode Sense—Pages 1D, 1E, 1F
  
  
• Move Medium
  
  
• Prevent/Allow Medium Removal (door access and IEPORT locking)
  
  
• Read Element Status
  
  
• Reserve, Release
  
  
• Send Volume Tag, Request Volume Element Address
  
  
• Test Unit Ready, Request Sense, Inquiry

Recommended: Inquiry with support for reporting serial number or other unique unit ID should be supported by the changer.