ServerNet Cluster Manual

ServerNet Cluster Description
ServerNet Cluster Manual—520575-003
1-4
Three Network Topologies Supported
Star Topology
The star topology, introduced with the G06.09 RVU, supports up to eight nodes and
requires two cluster switches—one for the X fabric and one for the Y fabric.
Because there is only one cluster switch per fabric, the position ID of each cluster
switch is always 1. Consequently, the cluster switches are named X1 and Y1.
Figure 1-2 shows both fabrics of an eight-node ServerNet cluster connected in a star
topology.
Note. You can configure a single system so that the software necessary for external
ServerNet communication is running and ready to communicate with other nodes. However, if
no other nodes are connected to the cluster switches, no communication occurs. In this case,
communication with remote nodes occurs as soon as the nodes are configured and connected.
Figure 1-2. 8-Node ServerNet Cluster Using Star Topology
VST039.VSD
ServerNet Nodes
8-Node ServerNet Cluster
(both fabrics shown)
NonStop Himalaya
Cluster Switch
NonStop Himalaya
Cluster Switch
X1
Y1
External
ServerNet
Y Fabric
External
ServerNet
X Fabric
Switch-to-Node Links
(80 meters maximum)