Domino Cluster

We have 2 servers in a cluster, Primary & Secondary. When I shut down Domino on the Primary server (but the Server is still on), users fails over to the Secondary. I look in the Secondary’s log and I see “Failing over from Primary…” which is great.

I did further testing and powered off the Primary server. When users tried to access their mailfile on the Primary, they get a “Server not responding” message, Lotus Notes did not failover to the Secondary. I look on the log it says "Unable to redirect failover from Primary.

Why can’t users failover when the Primary is powered off? Is there something that I am missing?

Thanks