Unable To Establish A Dlsw Circuit - 3Com MSR 50 Series Configuration Manual

Unable to Establish a
DLSw Circuit
segment. After both sides have established a correct route, the TCP connection
can be created.
Symptom
A DLSw circuit cannot be correctly established. The display dlsw circuit
command shows that the virtual circuit cannot come into CONNECTED state.
Analysis
Many reasons can cause circuit establishment failure.
A TCP connection with the peer end must be successfully established first.
■
If a TCP connect can be successfully established but circuit establishment fails,
■
the problem usually lies in the cooperation between the router and the SNA
device, mainly with SDLC configuration.
Solution
1 First enable the SDLC debugging, and check whether the SDLC interface can
receive/forward frames normally by executing the display interface command. If
the interface cannot receive/forward frames correctly, possible causes are incorrect
encoding scheme, baud rate or clock configuration on the interface. Modify the
interface configuration parameters of the router or adjust the configuration
parameters of the SDLC device.
2 If frames can be received and forwarded correctly, examine whether the
configuration of the PU type is correct. Use the sdlc xid command to configure
the XID and change the configuration of the PU type.
3 If the PU type is correct, use the display dlsw circuit verbose command to check
whether the virtual circuit can enter the CIRCUIT_EST state. If not, the MAC
address of the SDLC peer is not correctly configured. Use the sdlc mac-map
remote command to modify the configuration parameters.
4 If the circuit can reach the CIRCUIT_EST state, but cannot reach the CONNECTED
state, this means that the configuration of the SDLC on the router does not match
that of the SNA devices. Check the configuration of the SDLC devices on both
sides and the configuration of the router. For example, check whether the XID of
the SNA device is properly configured (PU2.1), and whether the XID of the router
is properly configured (PU2.0). If all these configurations correct, check whether
the SDLC line on the primary SDLC device side (such as the AS/400 or S390) is
activated. Sometimes the SDLC line needs to be activated manually.
Troubleshooting DLSw 233