If you clicke on "Backup" then you see a list box with "Incremental
(complete)". You can select "Always backup" to force a backup of all files,
including those which have not been changed since the last incremental backup.
However this way you create for all files an inactive version on TSM.

And if this is not what you want you may create an archive of the data.

Regards
Werner Nussbaumer