Hi George;
I use the 'move data' command to have TSM clear off an Offsite tape volume by,
as you mentioned, finding the files that TSM knows to be on that tape, and 
either
using an existing Offsite tape (that has yet to be moved Offsite) or opening a
new volume. It finds the files on the Onsite tapes and moves them to an Offsite
volume, so that the Offsite volume you did the 'move data' on is now devoid of
real data and can be trashed if necessary.
I run monthly backupsets on some nodes and, over time, the data for a specific 
client
node gets spread across perhaps 30 Onsite volumes.  For these, I do a 'move 
nodedata'
and it goes out there and finds these files spread over all there tapes and 
consolidates
it onto just a few volumes.

The short story - 'move data' to get files off a specific tape volume
                        'move nodedata' to consolidate files for a node to 
fewer volumes

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
George Huebschman
Sent: Friday, March 30, 2012 1:30 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Move NodeData

I think I have misunderstood how the command "move nodedata" works in regard to 
offsite media.
I had believed that it functioned in the same way that reclamation and move 
data operations worked, utilizing onsite media to write new offsite media.

This quote relates to  the "move data" command:
You can use this command to move files from an offsite volume in a copy storage 
pool or active-data pool. Because the offsite volume cannot be mounted, the 
server obtains the files that are on the offsite volume from either a primary 
storage pool, another copy storage pool, or another active-data pool. These 
files are then written to the destination volumes in the original copy storage 
pool or active-data pool.

I see nothing like that in the description of the "move nodedata" command.
It looks like I made a false assumption.
Is that so?
--
George Huebschman
Cell 301 875-1227

"When you have a choice, spend money where you would prefer to work if you had 
NO choice."