Expand Configuration and Management Manual (G06.24+)

Planning for ServerNet Clusters
Expand Configuration and Management Manual—523347-008
4-9
Examples of ServerNet Clusters Coexisting With
ATM or IP
ServerNet Clusters Using Layered Topology With
Connections to Nodes Outside the Cluster
In this example, all the systems directly connected to the cluster switches are NonStop
S-series systems. (See Figure 4-5.)
This ServerNet cluster uses the layered topology (for more information about the
layered topology, see the ServerNet Cluster 6780 Planning and Installation Guide ).
\Z123, \Z456, and \Z789 can be NonStop K-series servers (IP lines) or NonStop
S-series servers (ATM or IP lines).
The Expand line handlers in \BBB and \EEE (depending on $NCP’s determination of
the best-path route to \Z123) can become heavily stressed if other systems in the
ServerNet cluster frequently communicate with \Z123. (The same condition applies to
Expand line handlers in the ServerNet cluster nodes that communicate with \Z456 and
\Z789.) To avoid these potential bottlenecks, you can run ATM or IP within the
ServerNet cluster. Then, these lines are used to communicate with nodes outside the
ServerNet cluster.
Figure 4-4. ServerNet Clusters Connected by a Single ATM or IP Line (Not
Recommended)
\BBB #2
\FFF #4 \EEE #5
\AAA #1
\JJJ #8
Cluster
Switch
\CCC #3 \HHH #6
Cluster
Switch
\DDD #7 \GGG #9
5-Node ServerNet Cluster 4-Node ServerNet Cluster
ATM
or IP
VST063