brad@bert.chem.wisc.edu (03/26/91)
We have a VAX 4000/300 with a DEC KZQSA SCSI controller. The quotation for the system identified the controller as being for "CD=ROM and Tape". Nonetheless, we have a Fujitsu M2266S drive on it (we are at VMS 5.4, so there should be no problem with the size). The problem we do see is that, occassionally, there is a SCSI reset signal from someplace. This puts the disk in the infamous mount verify status. Within 10-20 ms it comes back. In ordinary operastion, I don't know of any serious problem resulting from this, although it is not good for it to happen at all. We also have an Exabyte 8200 on the same channel. We recently have been unable to complete neither a full nor an incremental backup of this disk onto 8mm tape. I suspect the mount verify problem (which is more frequent when doing the backup) is responsible for the problem while doing the full backup. I suspect that, during the incremental backup, there are pauses long enough for the 8mm tape to lose its position. Does someone know facts which can supplant/enhance my conjectures? If necessary, we can purchase a 3rd party SCSI controller, if the KZQSA will always give problems.