huge file, spanning multiple tapes

Jacques A. Vidrine nectar at
Thu May 1 15:23:57 PDT 2003

On Thu, May 01, 2003 at 05:03:18PM -0500, Dan Nelson wrote:
> How about tar?  That lets you specify a change-volume script so you can
> change tapes when you're writing, and when you read the tape later you
> can specify the --to-stdout flag so it doesn't write to disk.

Ah, I wasn't aware of the `--to-stdout' business.  That may do the
trick, though it is kind of hackish.  It only works because I already
have the file on disk, it seems.

> If you can't have any headers, 

I don't want them, but in this case it doesn't screw me up.

> you can always tell dd to only write
> 33GB per tape: 
> gzip < file | 
> (
>   dd of=/dev/ersa0 bs=64k count=$((33000000/64))
>   echo "please insert next tape"
>   head -1 < /dev/tty > /dev/null
> )

We don't know how much the tape would really hold.  It will likely
hold a good deal more than 33GB.

Thanks for the ideas!

Jacques Vidrine   . NTT/Verio SME      . FreeBSD UNIX       . Heimdal
nectar at . jvidrine at . nectar at . nectar at

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