Thanks to
Ronald D. Bowman
alan_at_nabeth.cxo.dec.com
Size of savesets: apparently, there is no simple way to find the size of
the savesets on tape. Knowing the blocksize at which media
was written it is possible to read back the file using 'dd':
dd if=/dev/nrmt0h of=/dev/null bs=60k
Knowing how many blocks are in a saveset it is possible to
calculate the its size.
Compression ratio: compare the size of the fileset and the corresponding saveset
on tape.
Advantages of NSR
(Networker): creates a catalog of every backup: will tell you which tape
the file you are looking for is on, sdpace to the saveset on
that tape, and space to the records holding that file.
can run multiple imput streams to a single output stream.
can do network backups of client systems.
supports media changes.
H/w vs s/w
compression: h/w (tape) compression is preferred to s/w (vdump) compression
(s/w compression uses CPU time). using both is most of the
time wasteful as it may create additional overhead on tape.
Received on Thu Aug 06 1998 - 23:14:04 NZST