3com 3031 Instruccion De Instalación

C

HAPTER

 36: DLS

W

 C

ONFIGURATION

It should be noted that on configuring router B, the MAC address of the remote 
end is just the MAC address of the AS/400 network card. But the MAC address 
should be configured in a inverse order, as the byte order of the Ethernet is inverse 
to that of the Token-Ring. If the peer end is Token-Ring, it needs not to be 
configured inversely. Neither need the virtual MAC address be configured in the 
host side of the tunnel. The c1 and c2 in the above example are PU2.0 typed 
devices, and the C3 is of PU2.1 type.

The normal communication of the DLSw needs sound cooperation of the involved 
two SNA devices and the two routers running the DLSw. Any fault in the 
cooperation between two nodes may cause connection failure.

Fault one: The TCP channel cannot be created and the displayed status of the 
display dlsw remote is DISCONNECT.

To create the TCP connection is the first step for successful DLSw connection. 
Failure in creating the TCP connection is the problem between two routers, 
generally due to wrong IP route configuration. The IP address of the remote can be 
checked to be reachable or not by the ping command with the source address. 
And the display ip routing-table command can also be used to examine whether 
there is route arriving at the network segment. After both sides establishing 
correct route, the TCP connection can be then created.

Fault two: The circuit cannot be correctly created and the virtual circuit cannot 
attain to CONNECTED status when the display dlsw circuit command is 
performed.

Many reasons can cause failure in creating the circuit. First of all, the TCP channel 
of the peer end should be ensured to be created successfully. After this 
requirement is satisfied, the circuit creation failure usually lies in the wrong 
cooperation between the router and the SNA device, mainly the wrong SDLC 
configuration.

First enable the SDLC debugging, and check whether the SDLC interface can 
receive/forward packets normally by performing the 

command. If it cannot receive/forward packets correctly, it is generally because of 
the faults in the coding scheme, baud rate or clock configuration on the interface, 
which can be solved by revising the interface configuration parameters of the 
router or adjusting the configuration parameters of the SDLC device.

If packets are received and forwarded correctly, examine whether the 
configuration of the PU type is correct. Use the 

 command to configure 

the XID and change the configuration of the PU type.

If the packets are received and forwarded correctly, use the 

 command to check whether the virtual circuit can enter the 

CIRCUIT_EST status. If it cannot all the time, it indicates that something is wrong 
with the cooperation between the configured virtual MAC address and the 
remote. This problem can usually be tackled by revising such configuration 
parameters as sdlc mac-map remote, etc.