When more than one node holds a lease, the overview's Server Memory
card gives way to Cluster Health: healthy nodes out of the total, the
number unhealthy, and each silent node named with how long it has been
quiet. It reads x:ClusterNode every 30 seconds and links to the node
list when the viewer may open it.
Healthy means Active. A server with the node heartbeat marks a node
Stale after three minutes without a lease renewal; older servers take
an hour. Inactive leases (a day silent) are left out. On a single
server, or without permission to list nodes, the dashboard is
unchanged.
jcoffey-dev