Cluster member reachability changed

Logged when a health probe adds a reachable member or detects the loss of a previously reachable member. It also reports reachable members removed by a successful configuration reload. The fields identify the node, its reachability and the resulting reachable member count.

If a member became unreachable, check its management listener, network connectivity and TLS trust. See cluster heartbeat settings.

Returning members automatically become eligible for availability-aware operations again.