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Troubleshooting using show controllers

Troubleshooting using show controllers 
9.3.6 
This page will teach students about troubleshooting using the show controllers command.
Router configuration and troubleshooting can be performed remotely when physical inspection of the connections is not possible. The show controllers command is useful to determine the type of cable connected without inspecting the cables. 
The output displayed by the show controllers command indicates the type of cable detected by the controller. This is useful for finding a serial interface with no cable, the wrong type of cable, or a defective cable.
The show controllers serial 0/0 command queries the integrated circuit, or controller chip, that controls the serial interfaces and displays information about the physical interface serial 0/0. This output varies for different controller chips.
Regardless of the controller chip type, the show controllers command produces a large amount of output. Other than the cable type, most of this output is internal technical detail about the controller chip status. Without specific knowledge of the integrated circuit, this information is of little use.
The Lab Activity will show students how to troubleshoot with the show controllers command.
The Interactive Media Activity will help students link network problems to the corresponding layer of the OSI model.
The next page will introduce the debug command.

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