To obtain information on UI availability of a node, the status operation can be used to determine if the node is running. If the
-u (clusterUrls) option is not provided the current node url is checked otherwise the urls provided will be checked.
When a node is disconnected from the cluster, the node itself should appear as disconnected and the cluster should have a bulletin indicating the disconnect request was received. The cluster should also show n-1/n nodes available in the cluster. For example, if 1 node is disconnected from a 3-node cluster, then "2 of 3" nodes should show on the remaining nodes in the cluster. Changes to the flow should not be allowed on the cluster with a disconnected node.
When the connect command is executed to reconnect a node to a cluster, upon completion the node itself should show that it has rejoined the cluster by showing n/n nodes. Previously it would have shown Disconnected. Other nodes in the cluster should receive a bulletin of the connect request and also show n/n nodes allowing for changes to be allowed to the flow.
When the remove command is executed the node should show as disconnected from a cluster. The nodes remaining in the cluster should show n-1/n-1 nodes. For example, if 1 node is removed from a 3-node cluster, then the remaining 2 nodes should show "2 of 2" nodes. The cluster should allow a flow to be adjusted. The removed node can rejoin the cluster if restarted and the flow for the cluster has not changed. If the flow was changed, the flow template of the removed node should be deleted before restarting the node to allow it to obtain the cluster flow (otherwise an uninheritable flow file exception may occur).