HP UX 11i v2 Networking Software manual Configurations with More Than 24 End Nodes

Figure 5-1 Single 24-port 376227-B21 Switch

376227-B21 Switch

24 Port HP Fabric Switch Configuration

A single 24-port 376227-B21 switch can be used to connect up to 24 HCAs. The maximum number of nodes that can be connected ranges from 3 (8 HCAs per node) to 24 (1 HCA per node). The figure above illustrates a configuration where all the ports of the switch are used. If the switch fails and an immediate repair of the switch is not feasible, it might be a difficult task to install another switch and redo the cabling. The cluster application that encountered errors may have to be down for a prolonged time until a new switch is installed and cabled to all the nodes. There is no transparent application recovery and it is recommended to bring down the application and restart only after ensuring the switch is functional again

Configurations with More Than 24 End Nodes

Where larger numbers of nodes are required, HP suggests cascading 376227-B21 24-port 4x Fabric Copper Switches (see Figure 5-2) or other configurations (see Figure 5-3and Figure 5-4).

Figure 5-2 36 Node 33% non-Blocking Configuration 2 Switch Cascade

This results in a configuration with 36-ports that are approximately 33% non-blocking, such that 18 ingress ports contend for 6 egress ports.

Sample Configurations using the AB286A/C or AD313A HCA 53