richk@june.cs.washington.edu (Richard Korry) (11/29/89)
I want to dump to a TK50. The Decstation 21/3100 Operator's Guide says that there are 600 ft of tape with 6667 BPI = 131 Mb per cartridge (unformatted) and the piece of paper that comes with the cartridge says 90 Mb (formatted). Ok, so far so good. I type the following to dump the file system: % /etc/dump 9dsu 6666 600 [more stuff] which says density = 6666bpi, size = 600 ft and the dump says: [stuff deleted] DUMP: Estimates based on 600 feet of tape at a density of 6660 BPI... DUMP: This dump will occupy 687 (10240 byte) blocks on 0.21 tape(s). [stuff deleted] Now 687 * 10240 = 7Mb. If this is .21 tapes then dump thinks that it holds 33Mb, not 90Mb. What's up?
richk@cs.washington.edu (Richard Korry) (12/01/89)
In article <82@e2big.dec.com> zemon@e2big.dec.com (Art Zemon SwsE/ACES) writes: >Try making your life much easier. Type "/etc/dump 9u {filesystem}" >and be done with it. Dump will use an ioctl to determine the >density and type of tape. In the interest of making my life easier I tried this and got: DUMP: Estimates based on 1200 feet of tape at a density of 6670 BPI... DUMP: This dump will occupy 691 (10240 byte) blocks on 0.11 tape(s). Which is fine excepy according to the spec sheet the tk50 cartridge holds 600 ft, not 1200 ft. If (691*10240) = 7Mb and that is .11 of the tape then the tape holds 64Mb or so. Again, the spec sheet says it holds 131Mb unformatted. If the answer is "dump is brain dead, ignore it." fine with me, I just don't want to run off the end of the tape or not use half the tape 'cause dump don't know whats what.
art@dinorah.wustl.edu (Arthur B. Smith) (12/05/89)
In article <10005@june.cs.washington.edu>, richk@cs.washington.edu (Richard Korry) writes: > In article <82@e2big.dec.com> zemon@e2big.dec.com (Art Zemon SwsE/ACES) writes: > >Try making your life much easier. Type "/etc/dump 9u {filesystem}" > >and be done with it. Dump will use an ioctl to determine the > >density and type of tape. > > In the interest of making my life easier I tried this and got: > [... Summary of wrong responses omittedi ...] > 131Mb unformatted. If the answer is "dump is brain dead, ignore it." fine > with me, I just don't want to run off the end of the tape or not use half > the tape 'cause dump don't know whats what. Don't sweat it. Dump (at least as provided with Ultrix 2.2 through 3.1) doesn't give a hoot about the predicted number of tapes. I never did set it, and always just remembered that one tape was about 1 1/2 nominal tapes. I would regularly get estimates of 1.3 tapes (or so) and have it all fit on one tape. art smith (art@dinorah.wustl.edu or ...!uunet!wucs1!dinorah!art) Usual disclaimers apply