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Implementing Cisco Networking Solutions by Harpreet Singh

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The debug commands

The debug commands are a very useful way of troubleshooting. It can help in identifying issues that a human eye can miss. For example, if two connected Cisco routers are configured to run OSPF using the passwords C!sco123 and C!sc0l23, the human eye might miss that the letter o is replaced by the numeral 0, thus leading to the protocol not establishing a neighbor relationship.

Running a debug command shows the packets exchanged and also shows messages on the console that can be interpreted to identify the issue.

Running a debug command can be a CPU consuming process and should be turned on only for troubleshooting.

Various types of debugs can be turned on the route. You can find a complete list by pressing the ? sign after ...

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