DLU licenses are no longer being sold. The user-based licenses will still generate a quantity of DLUs for < 9.0 systems; however, the legal entitlement is no longer the DLUs.
The minimum license required by a 6921 is a UCL Basic while a 7942 needs at least a UCL Enhanced. In your case you would need a quantity 28 of UCL Basic and quantity two of UCL Enhanced. Don't forget ESW/UCSS coverage.
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