CompuServe Messages

Paul, When something goes wrong on the SCSI bus, the results can be anything from innocuous to catastrophic. It depends on what's happening. Though the RDBs are not being accessed during a backup, it is quite easy to see how they might be clobbered, should the drive writ to block 0, since block 0 is the 'base' of the RDBs, and without it, the controller will think the drive does not have RDBs at all. Yes, the SCSI bus should be terminated at both ends. Usually, the host adapter is terminated, and if it is at one end of the chain, you need only terminate the other end. With the host adapter in the middle, if you terminate both ends of the bus, you will have three termination points, and things can get loaded down. Under these circumstances, the SCSI bus will often work with shorter cable lengths, and fail with longer ones (this is what gives SCSI termination a bad name). The answer in your case, I believe, is to ensure that only the ends of the SCSI bus are terminated. This can be accomplished in a few ways: 1. Daisy-chain the tape and disk, so that the host adapter is at one end of the cabling. 2. Leave it as is, but remove the terminators fromn the host adapter (may or may not be possible; I am not familiar with the TrumpCard). Often, one of the drives will be internal (yes, the internal one is on the same bus\, even if it's hooked to a fifferent connector). If the cable run is short enough, you can often get away with leaving it untermninated. According to the SCSI spec, you are allowed 'stubs' of not more that 10 cm., and experience has shown that if the total cable run is not too great, you can get away with longer stubs. I think you are on te verge of getting things fixed up. Good Luck. -larry