Continuing from the previous Example: (
Figure 91: A completed traceroute enquiry
on page 532), executing
traceroute
with an insufficient
maxttl
for the actual hop count produces an output similar to this:
Figure 92: Incomplete
traceroute
because of low
maxttl
setting
If a network condition prevents traceroute from reaching the destination
Common reasons for
traceroute
failing to reach a destination include:
• Timeouts (indicated by one asterisk per probe, per hop)
• Unreachable hosts
• Unreachable networks
• Interference from firewalls
• Hosts configured to avoid responding
Executing
traceroute
where the route becomes blocked or otherwise fails results in an output marked by
timeouts for all probes beyond the last detected hop. For example, with a maximum hop count of 7 (
maxttl
= 7),
where the route becomes blocked or otherwise fails, the output appears similar to this:
Figure 93: Traceroute failing to reach the destination address
Viewing switch configuration and operation
In some troubleshooting scenarios, you may need to view the switch configuration to diagnose a problem. The
complete switch configuration is contained in a file that you can browse from the CLI using the commands
described in this section.
Viewing the startup or running configuration file
Syntax:
write terminal
Displays the running configuration.
Chapter 13 Troubleshooting
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