Workgroup Servers: Causes of Stuck DAT Tapes

If a tape is stuck in a DAT drive, first make sure the indicator lights on the drive are not indicating an error condition:

Left (Cassette) Light	Right (Drive) Light	Meaning
Green	Pulsing Green/Amber	Media Wear
Amber	Amber	High humidity/SCSI termination
Pulsing Amber	Amber	Self-Test Failure

In some Workgroup Server 95 systems, tapes could not be ejected because of misalignment between the DAT drive and the front bezel.

A tape could be stuck because it is broken (no tension on the tape). It is unusual for this to happen but when it does, it's usually a fault of the mechanism not seating the tape all the way before starting the drive motors.

There are 2 fingers that contact each hub to make sure the tape does not unravel while in storage or out of the drive. When you insert a tape into the DAT drive, there are 2 covers that are moved (one covering the hub holes and one covering the tape surface). Upon insertion into the drive, the mechanism makes the covers open fully, thereby retracting the interposing fingers from the hub teeth.

If the fingers aren't pulled away from the teeth before the motors attempts to retension the tape, then the tape snags and most likely snaps. If you suspect this may be the problem, follow these steps:

1. Power down the server

2. Detach the SCSI connection to the DAT drive

3. Power up the server

4. Press in on the tape cartridge while depressing the eject button.

The other possible fault of DAT drives is the failure of the sensing mechanism to sense the end of tape. If this happens on EVERY tape that is inserted, then it's likely a hardware issue; if it's occasional, it may be a stiff cartridge not seating all the way in the mechanism or a faulty mechanism.

One final thing to check is how long a tape has been in use. The MRS tapes have a lifespan of about 50-60 hours of use, and should be replaced after that point.