System information

Troubleshooting IBM
Book Title
10-222
End system not
generating explorer
traffic
Step 1 Use the show source-bridge privileged exec command to see whether
the explorer count is incrementing.
Step 2 If the explorer count is not incrementing, use the show running-config
privileged exec command to view the router configuration. Check for a
source-bridge spanning interface configuration command on the local
and remote routers.
Step 3 If the source-bridge spanning command is not configured on the
routers, configure it on the interfaces connecting the local and remote
SRBs. This command is required if the end system is using single-route
explorers. The command syntax is as follows:
source-bridge spanning bridge-group[path-costpath-cost]
Syntax Description:
• bridge-group—Number in the range 1 to 9 that you choose to refer to a
particular group of bridged interfaces.
• path-cost—(Optional) Path cost for a specified interface.
• path-cost—(Optional) Path cost for the interface. The valid range is 0
to 65535.
Example:
The following example adds Token Ring 0 to bridge group 1 and assigns
a path cost of 12 to Token Ring 0:
interface tokenring 0
source-bridge spanning 1 path-cost 12
Encapsulation mismatch Step 1 Use the show interfaces exec command to verify that the interface and
line protocol are up. If the status line indicates any other state, refer to
Chapter 15, “Troubleshooting Serial Line Problems.”
Step 2 Verify that the configured encapsulation type matches the requirements
of the network to which the serial interface is attached.
For example, if the serial interface is attached to a leased line but the
configured encapsulation type is Frame Relay, there is an encapsulation
mismatch.
Step 3 To resolve the mismatch, change the encapsulation type on the serial
interface to the type appropriate for the attached network.
Hop count exceeded Step 1 Use the show protocol route command to check the hop count values on
routers and bridges in the path. Packets that exceed the hop count are
dropped.
Alternatively, you can enable the debug source event privileged exec
command to see whether packets are being dropped because the hop
count has been exceeded.
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.
Step 2 Increase the hop count if it is less than the default value, 7. Otherwise, the
network must be redesigned so that no destination is greater than 7 hops
away.
1 TCP = Transmission Control Protocol
Possible Problem Solution