Debug on Cisco

In this article, I will give an example of configuring and viewing debug information on Cisco switches. For an example and a test, I will take a Cisco Catalyst 6509-E switch.

First, turn off displaying logs in the console and sending them to a remote server:

no logging console
no logging monitor
no logging

Let’s clear the old logs so that they don’t interfere:

clear logging

We indicate the display of time in the logs with milliseconds:

service timestamps log datetime msec
service timestamps debug datetime msec
service timestamps debug datetime msec localtime show-timezone

Any of the commands below will enable the display of the necessary debug information:

debug ?
debug ip packet detail
debug ipv6 packet detail
debug arp

Let’s see the logs:

show logging
show log

After the necessary time, be sure to disable the recording of debug information to the logs:

undebug all

You can also change the size and level of logging from 0 to 7, where 0 is the minimum information:

logging on
logging buffered 0-7
logging buffered 4096-2147483647

0 – emergency: System unusable
1 – alert: Immediate action needed
2 – critical: Critical condition
3 – error: Error condition
4 – warning: Warning condition
5 – notification: Normal but significant condition
6 – informational: Informational messages
7 – debugging: Debugging messages

See my other articles about Cisco

Leave a comment

Leave a Reply