[99] in Info-AFS_Redistribution
Re: backup on rs_6k
daemon@ATHENA.MIT.EDU (Marybeth_Schultz@transarc.com)
Tue Apr 9 16:47:10 1991
Date: Tue, 9 Apr 1991 16:02:33 -0400 (EDT)
From: Marybeth_Schultz@transarc.com
To: kriso@northstar.dartmouth.edu, markf@northstar.dartmouth.edu,
Kris --
I just finished running fms on our RS6000 8mm tape drive and received
results very different from those you mentioned in your mail:
Dartmouth results:
wrote 35215 blocks
Tape capacity is 576962560 bytes i.e. 576M
File marks are 40030 bytes
Transarc results:
wrote block: 143135
Finished data capacity test - rewinding
wrote 11004 blocks, 11004 filemarks
Finished filemark test
Tape capacity is 2345189376 bytes
File marks are 196736 bytes
The tape capacity listed is ~2G which is what is expected on an
8mm tape. The filemark size is ~200k. Due to the drastic difference
in sizes that you received when you ran fms, it makes me wonder if your
tape received a write error during the fms run or if the tape is bad.
Allocating 40k to the filemark size is clearly not large enough,
which would account for the problems you saw. Please try using
the numbers I mentioned above and let me know the results.
Please note that if a tape is already written to, backup will continue
to use the "size =" value that was originally written to the tape
instead of the parameters listed in the tapeconfig file. A
"backup readlabel" command will display tape label parameters.
Tape label parameters can be changed with the "backup labeltape" command.
Finally, in your note you mentioned:
Since I had 2 out of 3 tapes work fine, I'm going to drop the
/usr/afs/backup/tapeconfig tape size parameter down to 1650Meg.
This is a drop of 100Meg from its current value which is much
greater than any volume size we have on our cell, ...
This in not correct. The tape capacity does not have to be larger
than any single volume in the cell. Volumes can be split across
tapes if necessary.
Please let me know if I can be of further assistance getting your
tapeconfig parameters working.
Marybeth Schultz
Product Support Specialist, File Systems
