topic Re: How can I write the header to tape? in Operating System - Linux

How can I write the header to tape?

Alfonso Rivera — Wed, 21 May 2003 21:53:30 GMT

Would you please tell me how to write the tape header? I mean, how can I label tapes? Any special command for that?

Thanks,
I will appreciate any help.

Re: How can I write the header to tape?

Steven E. Protter — Thu, 22 May 2003 02:20:01 GMT

I let the utility writing to the tape handle that.

tar writes by default directly to tape.
cpio can with the right command line switches.

SEP

Re: How can I write the header to tape?

Balaji N — Thu, 22 May 2003 03:27:02 GMT

hi
not sure if this is what you mean.

what we do normally during tape backups for easy identification, is to create a file which contains the backup script and the list of files and add it as the first file on the tape.

-balaji

Re: How can I write the header to tape?

Ralf Puchner — Fri, 23 May 2003 05:33:22 GMT

It depend on your tape system, but the "mt" command have some parameters to do that ;-)

Normally real backup software (taper, networker, veritas) will do the job automatically.

Re: How can I write the header to tape?

Sunil Sharma_1 — Fri, 23 May 2003 06:15:44 GMT

Hi,
I don't think u can do it by using normal unix commands like tar,cpio and dd.
but the backup software like Veritas Netbackup, OB and Networker write header/labale on disks.

Sunil

Re: How can I write the header to tape?

John Meissner — Fri, 23 May 2003 11:09:39 GMT

I don't know about linux (still looking into this). but in HP-UX you can use a few utilities to do this.

make_medialif -in HP-UX this creates the boot image file. Several command line options will allow you to "name" the tape and give a discription as well as several others.

in Linux I don't belive this utility exists. I'm sure there is a comparable program though.

Re: How can I write the header to tape?

John Meissner — Fri, 23 May 2003 11:19:27 GMT

What application are you using to create the tapes? have you tried a 'man' on that command to see if there are options to name the tape or put a descriptor on it?

Re: How can I write the header to tape?

Alfonso Rivera — Fri, 23 May 2003 21:05:51 GMT

Thank you all. The idea is to develop our own backup software and we would like that each tape have a label created by us in order to administrate the tapes.
The idea of Balaji seems good to me, but how can I insert a file at the beginning of the tape?

Re: How can I write the header to tape?

Ralf Puchner — Mon, 26 May 2003 09:10:15 GMT

The first step of the backup software is to create a catalog with the data which must be saved to tape. This is the phase the decision "full" or "incremental" will be made.
So create a list and write it to the tape followed by the real data.

btw. have a look into the source of "mt" to see how to init a tape.