Transferring tar files from one type of medium to another

[Andrew Kaplan]

Hello --

One of our systems is running HP-UX 11.11, and also utilizes gnu tar 1.19 as part of its backup procedure. Over the course of a decade, archiving has been done using tar to save files to a variety of tape media. This variety includes DLT, SuperDLT, and LTO-4 tapes.

We are going through the process of taking the content on the DLT and SuperDLT media, and transferring it to LTO-4 tapes. One method that we were going to use would have the administrators untarring the contents of the older tapes to a temporary folder, and then doing a tar of the temporary folder into the new tape.

One question came up was the following: Is it possible to simply copy the tar file, and in some cases multiple tar files, from the source tape to the destination tape without having to first going through the temporary directory?

Thanks.

[Dennis Handly]

>in some cases multiple tar files

Do you know which have multiple tarfiles and how many?

Ideally, you should be able to write a simple program that opens the tape (make sure it is rewound first).

Then read giant blocks.  Then write out as many bytes as read.

If EOF, write an EOF.

And finish on EOT.

This should work for just about any tape, except for copying the filemarks, which tar doesn't use but fbackup does.