There are several methods which can be used to prevent DLO Agents from performing backups to the NUDF.  The DLO Administrator needs to decide which method best fits his/her needs.

1. Implement a Blackout Window. The blackout window can be configured to prevent backups for a recurring period of time based on a schedule.
(From the DLO Admin Console > Tools >  Blackout Windows)

2. Disable individual Users.  This can be done very granularly.  Multiple users can be disabled simultaneously.
(From the DLO Admin Console > Setup > Users > rt-click on a User (or highlighted group of users) and select Disable)

3. Disable a Profile.  This can be done to target a group of Users all associated with the same Profile.
(From the DLO Admin Console > Setup > Profiles > rt-click on a Profile and select Disable)