Data Domain: Unable to Delete Orphaned DD Boost Users After Storage Unit Removal

DD Boost users cannot be deleted from either the CLI or GUI.
Attempts to delete or disable a DD Boost user fail with errors similar to:

Can not delete ddboost user "<example-user>".
Can not disable ddboost user "<example-user>".

Audit and SMS logs indicate the user is still recognized as a DD Boost user even though the associated storage unit has already been removed.
The environment contains fewer active storage units than DD Boost users, leaving orphaned DD Boost user accounts.

When PPDM policies are configured without selecting an existing storage unit, PPDM may automatically create new storage units and associated DD Boost users. If storage units are later deleted without completing the required file system clean process, stale metadata can remain within the file system. As a result, the DD Boost users continue to be referenced internally and cannot be disabled or deleted, even though their storage units no longer exist.

Verify that the associated storage unit has been removed.

Run a file system clean operation:

filesys clean start

Monitor the clean process until it completes:

filesys clean watch

Unassign the DD Boost user:

ddboost user unassign <username>

Note: The command may report that the user is already unassigned, which is expected in some cases.

Delete the user:

user del <username>

Repeat the process for any remaining orphaned DD Boost users.

After the file system clean operation completes, stale storage unit references are removed and the DD Boost users can be deleted successfully.