David Barcelo wrote:
I get this error every night. I have seen that several people have
been getting the same errors but I still don't quite understand why I
Several people? I've never seen them :-)
am recieving them. This looks like the culprit:
gzip: stdin: invalid compressed data--crc error
gzip: stdin: invalid compressed data--length error
It seems to me that your computer-cable-tape combination does not
work very reliable. Maybe random bits get changed in the stream
(while writing and/or reading).
First thing I suspect is hardware, like the cable (or the number of
goats you sacrificed while connecting them).
Isn't there some related message in /var/{adm,log}/{messages,syslog} ?
I would not trust any backup until found out what's the cause.
First try to see if the basics of your hardware is capable of reading
writing without errors. Do some torture test to see if you hardware
can write and read back a file many times without errors:
Generate a large file (74 * 1000000 = about 70 Mbyte)
nc localhost chargen | head -1000000 > dummyfile
Write this file to tape until end of tape
n=0; while dd if=dummyfile of=/dev/nst0 bs=32k;
do n=`expr $n + 1`;
done; echo wrote $n files to tape
Notice the number (the last file is not complete on tape).
Then read back the tape, and verify if the file compares the same:
mt rewind
m=0; while dd if=/dev/nst0 of=- | cmp dummyfile -;
do m=`expr $m + 1`;
done; echo Read $m files from tape
And try this a few times (writing/reading).
And maybe with/without hardware compression.
And maybe with another pattern as dummyfile.
Then add "gzip" to the test and try again.
--
Paul Bijnens, Xplanation Tel +32 16 397.511
Technologielaan 21 bus 2, B-3001 Leuven, BELGIUM Fax +32 16 397.512
http://www.xplanation.com/ email: Paul.Bijnens AT xplanation DOT com
***********************************************************************
* I think I've got the hang of it now: exit, ^D, ^C, ^\, ^Z, ^Q, F6, *
* quit, ZZ, :q, :q!, M-Z, ^X^C, logoff, logout, close, bye, /bye, *
* stop, end, F3, ~., ^]c, +++ ATH, disconnect, halt, abort, hangup, *
* PF4, F20, ^X^X, :D::D, KJOB, F14-f-e, F8-e, kill -1 $$, shutdown, *
* kill -9 1, Alt-F4, Ctrl-Alt-Del, AltGr-NumLock, Stop-A, ... *
* ... "Are you sure?" ... YES ... Phew ... I'm out *
***********************************************************************
|
