It Worked!

[Jerry LeVan]

Hello A/UX'ers

I have not been able to backup much of anything with the Apple
Tape Drive. This release (2.0) of A/UX seems to have buggered
the dump.bsd program ( the "c" option does NOT properly set
the backup options -- dump thinks that there are to many
blocks on the tape. The b and m options also do not conform
to reality. Richard Todd ( Bless you Richard) recommended lying
to the dump program by specifying density and length (in feet).

I am within epsilon over 2 of getting a tight fit.

Here is what I have done:

# dump.bsd -T5.2 0bsdf 8k 500 12500 /dev/rmt/tc1 /dev/dsk/c5d0s0
  DUMP: Date of this level 0 dump: Sun Oct  7 08:48:42 1990
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/dsk/c5d0s0 to /dev/rmt/tc1
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 67073 tape blocks on 1.89 tape(s).
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: 9.43% done, finished in 0:51
  DUMP: 17.22% done, finished in 0:49
  DUMP: 25.52% done, finished in 0:44
  DUMP: 34.17% done, finished in 0:39
  DUMP: 43.52% done, finished in 0:33
  DUMP: 50.55% done, finished in 0:30
  DUMP: Tape rewinding
  DUMP: Change tape: Mount tape #2
  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")

  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")

  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")
 yes
  DUMP: tape 2 begins with blocks from ino 2845
  DUMP: 51.12% done, finished in 0:34
  DUMP: 59.46% done, finished in 0:28
  DUMP: 67.47% done, finished in 0:22
  DUMP: 75.54% done, finished in 0:16
  DUMP: 85.05% done, finished in 0:09
  DUMP: 92.03% done, finished in 0:05
  DUMP: 100.44% done, finished in 0:00
  DUMP: Tape rewinding
  DUMP: Change tape: Mount tape #3
  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")

  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")
 yes
  DUMP: tape 3 begins with blocks from ino 4835
  DUMP: 104.70% done, finished in 0:-3
  DUMP: DUMP: 74525 tape blocks on 3 tape(s)
  DUMP: DUMP IS DONE
  DUMP: Tape rewinding
# mt -f /dev/rmt/tc1 status
Apple tc40 tape drive
total  4768 blocks (39059456 bytes) avail this cartridge
Last I/O was at blk 0
driver version 1.40

# mt -f /dev/rmt/tc1 status
Apple tc40 tape drive
total  4815 blocks (39444480 bytes) avail this cartridge
Last I/O was at blk 0
driver version 1.40

# mt -f /dev/rmt/tc1 status
Apple tc40 tape drive
total  4829 blocks (39559168 bytes) avail this cartridge
Last I/O was at blk 0
driver version 1.40

Hmmm, if the program thinks 500 ft @ 12500 bpi will write
67073 blocks in 1.89 tapes then it must think that there
are 35488.6 (1K) blocks per tape. So it thinks it can write
70.9 (1k) blocks / foot which is 8.87 (8k) blocks per foot
The Apple "standard" tape is 37.5 meg which is 4800 8k blocks
(Note above that not all tapes format out that large!)

Now 4800/8.872 = 541.02 ft would be required to get 37.5 meg

Let's give it a try and see it I can get the whole partition on
two tapes (taking care to use tapes with more that 4800 8k blocks)

# dump.bsd -T5.2 0bsdf 8k 542 12500 /dev/rmt/tc1 /dev/dsk/c5d0s0
  DUMP: Date of this level 0 dump: Sun Oct  7 16:22:47 1990
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/dsk/c5d0s0 to /dev/rmt/tc1
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 67131 tape blocks on 1.75 tape(s).
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: 9.50% done, finished in 0:47
  DUMP: 16.74% done, finished in 0:49
  DUMP: 25.12% done, finished in 0:44
  DUMP: 33.42% done, finished in 0:39
  DUMP: 41.34% done, finished in 0:35
  DUMP: 49.36% done, finished in 0:30
  DUMP: Tape rewinding
  DUMP: Change tape: Mount tape #2
  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")
yes
  DUMP: tape 2 begins with blocks from ino 3177
  DUMP: 55.37% done, finished in 0:28
  DUMP: 63.77% done, finished in 0:23
  DUMP: 72.16% done, finished in 0:17
  DUMP: 81.50% done, finished in 0:11
  DUMP: 89.40% done, finished in 0:06
  DUMP: 96.92% done, finished in 0:01
  DUMP: 106.37% done, finished in 0:-3
  DUMP: Tape rewinding
  DUMP: Change tape: Mount tape #3
  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")
  DUMP: NEEDS ATTENTION: Is the new tape mounted and ready to go?: ("yes" or "no
   ")
yes
  DUMP: tape 3 begins with blocks from ino 4897
  DUMP: 110.73% done, finished in 0:-7
  DUMP: DUMP: 74577 tape blocks on 3 tape(s)
  DUMP: DUMP IS DONE
  DUMP: Tape rewinding

@$##& still took three tapes
Almost nothing was written on the last tape for this last run.

I am starting to get the feeling that I am the only person in
the world who uses the Apple Tape Drive ( and I am starting to
understand why).

I still don't have a clue as to why "tar...| tcb > /dev/rmt/tc1"
fails immediately when the second tape is inserted...

Jerry
-----------------------------------------------------------------------------
| Jerry LeVan                           | Phone:(606)-622-1931              |
| Department of Computer Science        |                                   |
| Eastern Kentucky University           | Email:matlevan at eku.bitnet         |
| Richmond Ky 40475                     |                                   |
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|      "The series converges so slowly that it actually diverges."          |
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