> > My next question is, why do you dd to and from the tape, rather than let
> > xfsdump and xfsrestore access the tape directly?
>
> Because I seldom write directly to tapes. This is Amanda's job. Amanda
> writes dump/tar images in 32KB blocks to the drive starting with a 32KB
> ASCII text header describing the image and how to get it back from tape.
# dd if=$TAPE ibs=32k count=1
AMANDA: TAPESTART DATE 20011210 TAPE BE23
1+0 records in
64+0 records out
# dd if=$TAPE ibs=32k count=1
0+0 records in
0+0 records out
# dd if=$TAPE ibs=32k count=1
AMANDA: FILE 20011210 ente /export/software lev 0 comp N program
/sbin/xfsdump
To restore, position tape at start of file and run:
dd if=<tape> bs=32k skip=1 | /sbin/xfsrestore -f... -
1+0 records in
64+0 records out
This is really useful if you've got your tapes left only... W. Curtis
Preston calls it "bare metal recovery". I had a few "smoked" servers
where I was really happy to be able to operate with bare metal tools
like dd/tar/restore/xfsrestore.
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