HP Fabric Clustering System HP-UX Administrator's Guide, March 2008

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 5-3 and 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