[Techtalk] dump and compression

[Conor Daly]

Puzzled here...

I'm using dump to backup to CDRW.  If I do

dump -0 -B 665600 -f dump.dat /

I get a file dump.dat 650Mb in size.  That gets burned to CDRW before dump
continues and uses the same file for the next bit.  I can backup a 2Gb
partition in about 4 CDRWs.  If I use dumps compression option thus:

dump -0 -B 665600 -f dump.dat -z9 /

I get a file dump.dat about 215Mb in size and dump happily announces that
it hasachieved 3:1 compression.  But, I wanted dump to stuff as much
compressed data as possible into a _650Mb_ file!  Id there something I'm
missing?  I suppose I could use the tape length options to specify the
media size instead but it just don't feel right.

Conor
-- 
Conor Daly <conor.daly at oceanfree.net>

Domestic Sysadmin :-)
---------------------
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