Termination is built into the backplane. If you are getting an error that it is not terminated then I would try reseating the controller, cables, backplane, and HDDs. If that does not resolve the issue then see if the error still occurs with the HDDs removed. The issue can be caused by anything on the bus disrupting the signal, so it is not necessarily a backplane problem. The most likely part would be a backplane, but it could also be cables, HDDs, or the controller itself.
Dell EMC, Enterprise Engineer
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