Just re-read the documentation
http://download-west.oracle.com/docs...ckp.htm#455262
Excerpt :

Note that there is little value in creating multiple copies on the same physical media. For DISK channels, specify multiple values in the FORMAT option to direct the multiple copies to different physical disks. For sbt channels, if you use a media manager that supports Version 2 of the SBT API, then the media manager will automatically put each copy onto a separate medium (for example, a separate tape).


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Well, there is NO talk about having to allocate only ONE channel here (unlike the previous Note). Hmm..Apparently the new API will take care of plugging the 2 copies to separate media automatically.

Wonder how to verify this on sbt? I use TSM/TDP. Backups first go to FastT (disk) and something called collocation (tsm background process) copies it to tape later. Also, stuff gets moved around from one tape to another (within the tape library) in the background periodically. So if a certain piece were on tape10 today, it may very well be on tape20 the day after.

I wonder if there's any interface in TSM which tells you which piece currently resides on which tape.