paul@prcrs.prc.com (Paul Hite) (05/15/91)
We have some gaps in our understanding of DAT drives on systems running HP-UX 7.0. We have a list of questions that we have prepared to give to our support team. I thought that I'd post the list here in case anyone out there has the answers. All of these questions have been posed to various support channels in the past, but we either got no answer or many answers. 1) Model 1300H vs. unknown model used with 8x2 systems and hp-ux 7.0. We have discovered that we have two different types of DAT drives in McLean: the older 1300H used with CIO machines and a newer (?) model used in NIO machines. We have some documentation on the 1300H, but we have nothing on the newer model. What documentation is available? We have experimentally determined some of the differences, but is a complete list available? 2) How do we install hp-ux 7.0 on a 8x2 system with a DAT drive? Our understanding is that DAT's are not supported as an installation device with hp-ux 7.0. What is the supported way to recover from the loss of the system disk with hp-ux 7.0 on an 8x2 system? Can we obtain hp-ux 7.0 on DAT's? 3) The DAL 845's DAT will not work unless a cartridge is present at bootup. While this system was in McLean, we could use the DAT drive without having a cartridge present at bootup. Now that the system is in Dallas, this is no longer true. The local HP CE told us that a DAT drive will not work unless a cartridge is present at bootup. He has proven this with repeated tests. The response center says that a single error may be generated at bootup unless a cartridge is present, but this should not affect later operation of the drive (A1760715). The DAL 845 is in a state where the DAT drive is not usable unless a cartridge is present. How did it get in that state? We are prefectly willing to instruct all of our sites to have a cartridge in the drive at bootup time if this is required. But we want all (or most) HP personnel to come to an agreement on this issue. 4) What does patch p108 do? We are aware that a patch to tape1 is available and indeed we have the patch. The documentation that accompanies it is rather sparse. What does this patch change? We have not installed this patch permanently at any site. Should we? 5) Can we use /dev/rmt/0mn on a 1300H in emulation mode? We have heard many answers to this question. The application note (C1511-90906) says no in gray box inside front cover and again on page 6. Then on page 9 it says that "mt" may be used to position the tape. It has examples like "mt -t /dev/rmt/0m" which would seem to be a no-op. The example "mt -t /dev/rmt/0m fsf 4" would seem to be impossible unless the restrictions in that gray box were lifted. All of the discussion of "mt" on page 9 is clearly implying that multiple files on one tape are possible. We have tried using the no-rewind bit and it seems to work. One HP source told us that time-outs could result if we used the no rewind bit. Another told us that it simply wasn't tested and might well work. As an aside, page 9 of the application note says that "mt" may be used to eject the cartridge under software control. How is this done? Paul Hite PRC Realty Systems McLean,Va paul@prcrs.prc.com (703) 556-2243 You can't tell which way the train went by studying its tracks.