Expand Configuration and Management Manual (G06.24+)

Configuring Expand-Over-ServerNet Lines
Expand Configuration and Management Manual—523347-008
12-3
Modular ServerNet Expansion Boards (MSEBs)
MSGMON is a persistent process. Once it is started, it terminates only in the event of
an internal failure or a termination message from the persistence monitor, $ZPM.
MSGMON is not a process pair.
Modular ServerNet Expansion Boards (MSEBs)
MSEBs provide connections for ServerNet cables that link one system enclosure to
another. Unlike SEBs, MSEBs use plug-in cards (PICs) to provide a choice of cable
media for routing ServerNet packets. Two MSEBs are required for each node, one for
the external ServerNet X fabric and the other for the external ServerNet Y fabric.
Network Access Method (NAM)
NAM is a pair of message system dialects that allow use of another process, such as
X.25, SNAX, or FOX, as an Expand communications medium. NAM contains
connection establishment, data transfer, and disconnection phases. For more
information, refer to Expand-to-NAM Interface on page 18-49.
Network Control Process ($NCP)
The network control process ($NCP) initiates and terminates server-to-server
connections and maintains network-related system tables, including routing
information. $NCP must be running at every node in the Expand network before
Expand lines can be started.
Cluster Switch
A cluster switch is a 12-port network switch designed for use in ServerNet networks. In
a ServerNet cluster, a cluster switch provides the physical junction point that enables
multiple nodes to connect to the network. For more information about the cluster
switch, refer to the ServerNet Cluster Manual (for the 6770 cluster switch) or the
ServerNet Cluster 6780 Planning and Installation Guide .
Profile Products
To create a ServerNet cluster that operates with other Expand line types, order
individual profile products for the line types you are using. Profile products include
those in Table 12-1:
Note. MSGMON is compatible only with G06.09 and later RVUs of the NonStop Kernel
operating system.