OpenVMS Cluster Systems - OpenVMS Systems - HP

Sample Programs for LAN Control
D.5 Using the Network Failure Analysis Program
Table D–2 (Cont.) Creating a Physical Description of the Network
Step Action Comments
4 Classify each component into one of the following
categories:
• Node: VAX or Alpha system in the OpenVMS
Cluster configuration.
• Adapter: LAN adapter on the system that
is normally used for OpenVMS Cluster
communications.
• Component: Generic component in the network.
Components in this category can usually be
shown to be working if at least one path through
them is working. Wiring concentrators, DELNI
interconnects, DEMPR repeaters, LAN bridges,
and LAN segments and rings typically fall into
this category.
• Cloud: Generic component in the network.
Components in this category cannot be shown to
be working even if one or more paths are shown
to be working.
5 Use the component labels from step 3 to describe
each of the connections in the OpenVMS Cluster
communications network.
6 Choose a node or group of nodes to run the network
failure analysis program.
D–6 Sample Programs for LAN Control
The cloud component is necessary only when
multiple paths exist between two points within the
network, such as with redundant bridging between
LAN segments. At a high level, multiple paths
can exist; however, during operation, this bridge
configuration allows only one path to exist at one
time. In general, this bridge example is probably
better handled by representing the active bridge
in the description as a component and ignoring the
standby bridge. (You can identify the active bridge
with such network monitoring software as RBMS
or DECelms.) With the default bridge parameters,
failure of the active bridge will be called out.
You should run the program only on a node that
you included in the physical description when you
edited LAVC$FAILURE_ANALYSIS.MAR. The
network failure analysis program on one node
operates independently from other systems in the
OpenVMS Cluster. So, for executing the network
failure analysis program, you should choose systems
that are not normally shut down. Other good
candidates for running the program are systems
with the following characteristics:
• Faster CPU speed
• Larger amounts of memory
• More LAN adapters (running the NISCA
protocol)
Note: The physical description is loaded into
nonpaged pool, and all processing is performed at
IPL 8. CPU use increases as the average number of
network components in the network path increases.
CPU use also increases as the total number of
network paths increases.