Debug Command

[PacNWNetTek]

Hello everyone,

Entry-level technician here trying to learn/use the debug command. I have a cisco c3560cx access layer switch that is not allowing DHCP through to devices on a particular VLAN, even ones with reserved addresses. I'm confident I know what the issue is but I would like to try and confirm it via debug. I have tried a few from research but the switch isnt "spitting" out any debugging info. Not sure if im doing it right so any commands I could use and results I should see is greatly appreciated. I also have a off network switch for practice (2960-X) so any processes you can give that I can use hone this skillset is also appreciated. 

P.S. Terminal monitor is on.

[balaji.bandi]

you can use the below command :

debug dhcp detail 
debug ip udp
debug ip dhcp server packet
debug ip dhcp server events

here is a good document which explains how to debug DHCP request :

https://www.cisco.com/c/en/us/support/docs/ip/dynamic-address-allocation-resolution/27470-100.html

[paul driver]

Hello

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@PacNWNetTek wrote:

I would like to try and confirm it via debug. I have tried a few from research but the switch isnt "spitting" out any debugging info.

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Just like to add you need to enable logging to see the messages
logging console <level> <--- will show message logs when your attached to device via console
logging monitor <level> <--- will show message logs when your attached to device via vty lines
logging buffered <level> <--- will log messages to the internel buffer of the device ( show logging)


Also would suggest to add some timestamps for validation..
service timestamps log datetime localtime msec show-timezone
service timestamps debug datetime localtime msec show-timezone