TCP/IP Management Programming Manual

Introduction
HP NonStop TCP/IP Management Programming Manual—529636-001
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SUBNET Object
Subsystem Control Point (SCP). The PROC object must be a NonStop Kernel named
process.
A NonStop system can support multiple TCP/IP processes. Each process has a unique
IP address and is handled as a separate subsystem. Typically, a NonStop system
attached to a TCP/IP network has only one TCP/IP process. However, when a
NonStop system that contains multiple processes is attached to an IP network, each of
the processes must appear as a separate host with a unique address on the IP
network.
System configuration is not required for the TCP/IP process. Create the process with
the RUN command.
An example of a command for creating a TCP/IP process:
1>RUN $SYSTEM.SYS03.TCPIP/NAME $ZTC0,NOWAIT,CPU 0/
Once the process is created, you can add subnets and routes. Adding routes is
optional because the TCP/IP subsystem automatically adds a route when you add a
subnet with the ADD command.
SUBNET Object
The SUBNET object defines the IP layer attachment point to either the SLSA
subsystem or the X.25 I/O process (X25AM). It is through the SUBNET object that data
can be sent to and received from either the Ethernet (DIX) LAN, IEEE 802.3 Ethernet
LAN, IEEE 802.5 token ring LAN, or the X.25 network. For Ethernet and SNAP
subnets, the SUBNET object in the TCP/IP subsystem is associated with a logical
interface (LIF) in SLSA. For X.25 subnets, the SUBNET object in the TCP/IP
subsystem is associated with a LINE object in X25AM. Subdevices on this X25AM
LINE object are opened by the TCP/IP process.
You can add a maximum of 17 subnets to each TCP/IP process: 4 Ethernet subnets, 8
SNAP subnets (4 token ring and 4 Ethernet), 4 X.25 subnets, and 1 loopback driver.
When adding subnets, follow the DSM naming conventions.
ROUTE Object
The ROUTE object specifies the path used to transmit IP datagrams between the
TCP/IP subsystem and the destination. The route specifies both the destination and
the next gateway or host to which a datagram must be sent to reach the destination.
The IP Layer at each host maintains a table of routes. The table lists the internetwork
address of each accessible network or accessible host on a network. In addition, the
table lists the gateway to be used to reach that network or host. A host’s routing table
often specifies a default gateway to which datagrams can be sent if the routing table
does not contain an entry for a particular network. If the default gateway is used, the
Note. For NonStop availability considerations, you must carefully plan before adding multiple
subnets to a single TCP/IP process. For detailed information about NonStop availability
considerations in this release, see the TCP/IP Configuration and Management Manual.