Expand Configuration and Management Manual (G06.24+)

Planning for ServerNet Clusters
Expand Configuration and Management Manual—523347-008
4-4
Examples of ServerNet Clusters Coexisting With
FOX Rings
Examples of ServerNet Clusters Coexisting With FOX Rings
The ferris-wheel topology is recommended when a ServerNet cluster needs to coexist
with a FOX ring. This topology provides fault-tolerant communication between all
nodes, high performance, low processor utilization, and low message latencies.
The following examples are provided in this subsection:
•
ServerNet Cluster Inside a FOX Ring on page 4-4
•
ServerNet Cluster and FOX Ring Connected By One NonStop S-Series System
(Not Recommended) on page 4-5
ServerNet Cluster Inside a FOX Ring
When NonStop S-series systems are combined with NonStop K-series systems in a
FOX ring, you should add the NonStop S-series servers to the FOX ring as well as to
the ServerNet cluster to reduce message latency for transmissions between the two
server types. By adding the NonStop S-series servers to the FOX ring, the NonStop
S-series servers can communicate with each other by using clustering technology and
can communicate with the NonStop K-series servers by using the FOX ring. Using the
same communication technology to communicate between the different server types
reduces latency and speeds transmission times by eliminating a line hop.
For example, if you have four FOX-connected systems, two of which are NonStop
S-series servers and two of which are NonStop K-series servers, and you want to add
four NonStop S-series servers and ServerNet clustering technology, adding the new
servers to the FOX ring as well as to the ServerNet cluster speeds transmission times
by allowing the NonStop S-series servers and NonStop K-series servers to
communicate with each other over FOX. This configuration, shown in Figure 4-1,
eliminates the line hop that would occur to switch from the ServerNet cluster to the
FOX ring for messages travelling between the different server types.