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Filtering tcpdump: Creating order from chaos

Learn to use tcpdump's filtering capability to make it easier to make sense of your network data in this quick, informative tutorial.
In my last article, Troubleshooting with tcpdump, I looked at the tcpdump
tool, some basic use cases, and walked through a mock-up of a real-world scenario. Now, I want to dig a bit further. Everyone who uses this tool in a real situation immediately notices how much information (I believe they call this "verbose"...) is presented to the user. One of the best things you can do for yourself is figure out a practical way to filter for the information you need. Let's look at some ways that you can do this.