Troubleshooting IBM - Internetworking Troubleshooting - page 291

Table 10-11 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table10-10 SDLC: Client Cannot Connect to Host over Router Running SDLLC

Possible Problem Solution

SDLC physical or
data link layer
problem

Use the show interface slot/port exec command to check the
state of the connection with the SDLC device.

1.

Look for USBUSY in the output, which indicates that the
router is attempting to establish an LLC connection. If the
router is not USBUSY, make sure that the physical and link
layers are working properly. For more information, refer to
the section “SDLC: Router Cannot Communicate with
SDLC Device,” earlier in this chapter.

2.

If the router is USBUSY, proceed to the next problem in this
table.

3.

Router that is not
sending test
frames to FEP 1

1. With the debug sdllc and debug llc2 packet privileged exec
commands enabled on the router, check whether the router is
sending test frames to the FEP.
Caution: Because debugging output is assigned high priority in
the CPU process, it can render the system unusable. For this
reason, use debug commands only to troubleshoot specific
problems or during troubleshooting sessions with Cisco
technical support staff. Moreover, it is best to use debug
commands during periods of lower network traffic and fewer
users. Debugging during these periods decreases the likelihood
that increased debug command processing overhead will affect
system use.
2. If the router is sending test frames to the FEP, proceed to the
next problem in this table.
3. If the router is not sending test frames to the FEP, use the
show running-config privileged EXEC command to view
the router configuration. Make sure that the sdllc partner
interface configuration command is present.
4. If the sdlc partner command is not present, add it to the
configuration. Make sure that it points to the hardware
address of the FEP on the Token Ring. The following is the
syntax for the sdlc partner command:
sdlc partner mac-address sdlc-address
Syntax description:
•

mac-address —48-bit MAC address of the Token Ring host.

•

sdlc-address —SDLC address of the serial device that will
communicate with the Token Ring host. The valid range is 1
to FE.