Overnight we experienced a failure of DS-178 is BOL23 datacentre.
Unfortunately, within a few seconds of this failing, we also experienced a network interface failure on another device within the network ring when it changed state from failover to active. This caused an isolation of various network devices within BOL23.
We replaced DS-178 and corrected the isolation event. We will expedite our migration from these older network switches over to our newer resilient network.