The Loopback Network Interface Configuration screen (#97)
in Figure 13-3 “Loopback Network Interface Configuration
Screen” is displayed when
you select an NI name and the NI type LOOP
at the Network Interface Configuration screen (Figure 13-2 “Network Interface Configuration”) and press the [Add]
or [Modify] function key. It is also displayed
when you type the path name:
@NETXPORT.NI.NIname
in the command window of any screen and press the [Enter]
key, where NIname is a configured loopback
NI.
Figure 13-3 Loopback Network Interface Configuration
Screen
![[Loopback Network Interface Configuration Screen]](img/gfx113.gif)
Whenever a transport user makes a connection to a user process
on the same node, all outbound packets on this connection are turned
around at the NI level and passed back up through the protocol stack
to the destination user. This screen supplies information necessary
for this operation, performed by the loopback NI.
Press the [Save Data] function key to transfer
the data displayed on the screen to the configuration file you are
creating or updating. Verify that the data record has been created
by checking that the Data flag is set to Y.
Fields
- Network segment size (bytes)
(HP modifiable.) This is
the size of the physical buffer for the loopback network interface.
No fragmenting or fragment assembly is performed on the loopback
NI. There is no limitation that only single physical buffers (not
chained buffers, for example) can be passed across the I/O interface
to the board, because outbound data is turned around at the NI layer.
Therefore, if user data exceeds the physical buffer size, it is
put into logical buffers (chained physical buffers) that are the
size of the user data.
Default value: 1024
Range: 1024-4032
- Number of outbound buffers
This field specifies the number of outbound buffers
to be allocated for loopback. The default is based on the assumption
that the network manager desires to allow no more than the default
number of TCP connections (128) to use the loopback NI. Therefore,
the default is 128. If you change the number of TCP connections
from the default value, you should reconsider the number of inbound
buffers for all NIs.
Default value: 128
Range: 128-1024
