file position on a tape

[mac_cs]

Hello,
I am writing a script to read data from a TSM HSM server. I am using scp command to the AIX server to copy the files. I know where the each file resides and have sorted the files in tape order. I wanted to further optimize the reading by arranging my requests in the order the files are stored on the tape. Is it possible to get the position of a file on a given tape?
I am sure it is kept somewhere in the TSM database, but I am no expert in TSM. When I did such a migration from SUN SAM-FS, I did use the file position on the tape to organize my requests.

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[moon-buddy]

This is what I know about TSM tape management:

The metadata - meaning the information about the file - is stored in the TSM database. The metadata contains the location of the file in relation to the tape label. As for the exact position within the tape, this lies with the tape itself.

Being the case, the exact location within a tape is not known by the TSM database. Most tape formats carry a TOC which in turn has the information on file specifics within the tape itself.

If your reference to your experience with SUN, and if I presume correctly you used SUN's ufsdump and ufsrestore routine, it is easy to track where on the tape a file or sets of files lies. The files are separated by markers (EOF, BOT, etc.) making it easy to track. I used this method in the past to track file backup and restores.

Again, this is as far as I know how TSM handles files on tapes.

 

[mac_cs]

........

The metadata - meaning the information about the file - is stored in the TSM database. The metadata contains the location of the file in relation to the tape label. As for the exact position within the tape, this lies with the tape itself.

........

This is the information I need, as long as I arrange my file requests to the TSM HSM in the order the files are stored on the tape, I can stream the tape. Do you know the command to dump this information to a flat file? or do you have the table information for this? i am a newbie as far TSM is concerned.

Thanks again for the reply.

 

[moon-buddy]

I am no expert on this, and I don't know the commands. I am afraid you are on your own.

Good luck.

 

[mac_cs]

ok, here is what I ended up doing. We could not find the location of the file on the tape. Then we looked for date/time the file was archived. We arranged the files according to date/time stamp the files were archived and pulled the files in that order and it worked perfect. I used a friend of mine who know TSM and he got the info for me, I dont know what command he used.

 

[moon-buddy]

Sure this will work. However, your original requirement of knowing where exactly the files are on the tape was not addressed.

Come to think of it, why would you want to know exactly where on the tape a file resides if you know the time/date it was backed up?

 

[mac_cs]

actually, the original request was to know the order in which the files are stored on the tape so I can stream them. I thought of location, but time archived actully gives the same inforamtion. If I were to sort on the archieved time in acsending order, I achieved waht i was looking for.
Thanks for engaging in this thread.