At 02:42 PM 3/6/2001, John R. Jackson wrote:
> >By the way...how does amanda's software compression factor into this?
>
>You have to know if the image is compressed or not and insert the
>appropriate uncompress command in the pipeline (or, as a special case,
>use the GNU tar 'z' option, which does that for you).
>
>Note that the image header (the first 32 KByte block of the file) tells
>whether the image is compressed or not. For that matter, it tells you
>the exact command sequence to use to recover the image.
Ach!! I am close, I can feel it... I was playing around waiting
for replies, and I did the following:
mt -f /dev/nst0 rewind
dd if=/dev/nst0 bs=32k count=1
dd if=/dev/nst0 bs=32k count=1
dd if=/dev/nst0 bs=32k count=1
the first one showed me:
AMANDA: TAPESTART DATE 20010227 TAPE Daily3
1+0 records in
1+0 records out
the second gave me:
0+0 records in
0+0 records out
and the third produced:
AMANDA: FILE 20010227 backup.diligence.com /pkgs lev 0 comp .gz program
/bin/gtar
To restore, position tape at start of file and run:
dd if=<tape> bs=32k skip=1 | /usr/bin/gzip -dc | bin/gtar -f... -
1+0 records in
1+0 records out
-=BUT=-
when I do:
mt -f /dev/nst0 rewind
mt -f /dev/nst0 fsf 02
I get an I/O error...
same as if I "mt -f /dev/nst0 fsf 2"
So, then I tried
mt -f /dev/nst0 rewind
mt -f /dev/nst0 fsf 1
mt -f /dev/nst0 fsf 1
I also get an I/O error...
Then I tried to dd the first two to /dev/null
and the third time I do
dd if=/dev/nst0 bs=32k skip=1 | /usr/bin/gzip -dc | bin/gtar -f... -
I see:
dd: /dev/nst0: I/O error
0+0 records in
0+0 records out
gzip stdin: unexpected end of file
Am I going to need to identify the start and end of this file and do it by
count?
dd if=/dev/nst0 bs=32k skip=1 count=NN | /usr/bin/gzip -dc | bin/gtar -f... -
where NN is the number of blocks in the file?
Thank the higher powers that I'm dealing with this now as a test run
and not later in an emergency...I would have been killed by now :o)
Jer
