When it comes to troubleshooting network related issues on a Linux host, often times, the first step most administrators take is disabling the host-based firewall. Did you know that this imposes security risks? What if the host-based firewall wasn’t the issue and it was actually tcp wrappers? Or, what if a process was only listening on localhost? As the list of things to check and troubleshoot grows, what if we can use a tool like tcpdump to make the job easier?
In this talk, we will cover:
- An overview of what tcpdump is.
- The installation of tcpdump.
- Explore the tcpdump cli flags.
- How to interpret the output.
- How to write basic capture filters.
- Provide you with real world use cases and examples.