Offload of tapes

[Vito Sarducci]

I have a very peculiar technical problem i need some guidance on. I have a 8mm tape drive, ie exabyte 8205xl and a 4mm tape drive.

What I need to do is take the 8mm tapes and offload them to the 4mm tapes. My question to all of my fellow guru's in-house is how can i do this and what "unix" level utilities can i do this with?

The reason why I say unix is that I will have to do this on multiple systems besides my HP's in house. I have a Tru64 unix system, HP-Ux and Sco-unix that I will need to do this with.

Are there any good utilities on the web or thru anyone here that I can use to accomplish this project?

I would prefer to just do a dump of the the 8mm to a disk and then disk to tape on the 4mm.
Time is not an issue, so the easier it is works for me.

Any feedback is highly welcomed?

Vito

[Alexander M. Ermes · Accepted solution]

Hi there.
What about the good old dd ?

dd if=8mmtape of=4mm tape ....
Rgds
Alexander M. Ermes

[John Palmer]

Hi,

dd will do the job but you need to consider the following (all of which require some detailed knowledge of the data held on the input tape):-

- dd's blocksize (bs=n) MUST be set to a value at least equal to the size of the largest block on tape. If the blocksize is not large enough then data will be lost and dd will report the number of partial blocks read (see DIAGNOSTICS in the man page).

- There may be more than one file on the tape. For instance, fbackup writes at least two. The best approach is to write a script that does dd in a loop and exits when dd fails because it has reached the end of the input tape.

- Does the output tape have sufficient capacity to hold the contents of the input tape? If not (and it's a single tape file) then you can't simply copy tape to tape although if it's a backup tape, you could restore it to disk then back up the restored data to the intended output tape.

Hope this helps.

John