CDP Discovery Using Microsoft’s PKTMON

In this video, I review how to use Microsoft pktmon commands to figure out what port I am connected to without using Wireshark.

Tony Fortunato

February 18, 2022

In previous articles, I have covered some of what I consider troubleshooting best practices and got back some helpful feedback.

One person asked me, “is there a way to figure out what port I am connected to without using Wireshark?”  Wow! What a great question. Challenge accepted.

In summary, here's what I did: I used the Windows Packet Monitor (Windows pktmon) command to capture only packets addressed to Cisco’s multicast mac address, converted the trace to a text file, then used Microsoft’s find command to get the info I needed.

In this video, I review a little of the Microsoft Prompt usage and then get into pktmon commands. When using pktmon, it is critical to confirm that you don't have any filters already loaded. I have found that pktmon remembers your filters, even after you reboot your computer. The other important thing to verify is the numeric value that points to the network card you wish to capture from.

Here is a list of the commands I used in the video for your reference.

About the Author(s)

Tony Fortunato

Sr Network Performance Specialist

Tony Fortunato is a network performance expert who has been designing, implementing and troubleshooting networks since 1989. His company, The Technology Firm, provides clients of all sizes with services ranging from project management, network design, consulting, troubleshooting, designing custom-designed training courses, and assisting with equipment installation. Tony's experience in networking started with financial trading floor networks and ISPs, where he learned to integrate and support equipment from various vendors. Tony has taught and presented at numerous colleges and universities, public forums and private classes. He blogs frequently at NetworkDataPediaand has a popular YouTube channel.

Stay informed! Sign up to get expert advice and insight delivered direct to your inbox

You May Also Like

More Insights