N+1 Configuration

In an N+1 configuration, one node is the backup for all other nodes in the cluster. Table 4-2 shows the logical host distribution for a four-node N+1 configuration with three logical hosts. In this configuration, upgrade node 4 first. After you upgrade node 4, it can provide all services while nodes 1, 2, and 3 are upgraded.

Table 4-2 Three Nodes With Three Logical Hosts

	Logical Host 1	Logical Host 2	Logical Host 3
Node 1	X
Node 2		X
Node 3			X
Node 4	X	X	X