HP StorageWorks 4000s NAS 4000s and 9000s Administration Guide - Page 25

System Overview NAS Server Cluster Deployment In a clustered deployment, network connections are divided into three categories: cluster maintenance segments, client data segments, and management segments. The default shipping configuration contains a two-port 10/100/1000 NIC that together provide one port for the cluster maintenance and one port for management and client data. An additional management port for remote console and diagnostics is provided off of the iLO port. HP recommends that this connection be placed on a management LAN separate from the corporate infrastructure. The cluster maintenance segment is also known as the heartbeat connection between the nodes. In standard configurations, this connectivity is obtained by the use of a crossover network cable. The same effect can be achieved by placing the heartbeat ports on its own switch or VLAN, as illustrated in Figure 4 as Eth1. The purpose is to isolate and guarantee the connectivity between the nodes without interruption. If interruption occurs, the remaining cluster node will assume the other node has gone down and initiate a failover. A second cluster heartbeat path is often recommended as a redundant path. The redundant path is often done over one of the remaining network segments and is not dedicated. The client data segments of a cluster must reside on identical network segments for each node. As illustrated in Figure 4, Eth2 from both nodes is shown on the same segment. This co-location on the same segment allows cluster resources such as file shares to failover to the second node and continues to provide availability to the resources. The failed resource will have the same IP address after the failover and therefore must have a port corresponding to the identified subnet of the IP address present on both nodes. The NAS server supports the use of NIC teaming in clustered configurations. All previous caveats from the "NAS server single node deployment" on networks section still apply. Integrated Lights-Out Port Management and Client Data Network Eth 2 Cluster Node A Cluster Heartbeat Eth 1 Node A HBA 1 Node A + HBA 2 ++ + ++ + + ++ Node B + HBA 2 Node B HBA 1 SAN Switch SAN Switch Cluster Node B Cluster Quorum Mirrorset LUN 1 Storage Area Network Data RAID set Node A LUN 2 Data RAID set Node B LUN 3 Figure 4: NAS server cluster deployment NAS 4000s and 9000s Administration Guide 25