How to Merge Wireshark Capture Files: A Simple Way to Combine Packet Captures

When troubleshooting a network problem, you don't always end up with one convenient Wireshark capture file. Sometimes you have multiple packet captures taken from different interfaces, different locations, or different points in time. Instead of opening each file separately and trying to piece everything together, Wireshark can merge multiple capture files into a single file. This can make analyzing a complicated network problem considerably easier, especially when you need to compare traffic from multiple sources.

WiFi vs LAN: What Actually Happens When You Plug In Ethernet?

A client of mine recently raised a great networking question while we were planning a new laptop build: what actually happens when a machine is already connected over WiFi and you then plug in Ethernet—whether that's a docking station, a USB dongle, or the built-in port? It's a classic "it depends" scenario, and it's the kind of WiFi vs LAN question that gets debated far more often than it gets tested. If you've ever wondered which connection your laptop prioritizes, the answer is worth verifying yourself rather than trusting secondhand claims.

Wireshark Windows Adapter Issue and Fix

I was trying to capture packets from my Network Critical SmartNA packet broker and only saw broadcast packets.

At first, I blamed the packet broker since I assumed I knew my laptop and Wireshark so well. Do you know what they say about the word 'assume'? ;)

Pros and Cons of Packet Slicing

Whenever I’m working with a client on packet analysis, I always ensure that I cover packet slicing concepts. It doesn’t matter if I am teaching, troubleshooting or baselining, I believe that packet slicing is an important part of packet capture.

One school of thought is to slice after the fact, which you can do with Wireshark’s editcap utility and the -s option and now you have the original trace and a sliced one. Unfortunately, depending on the size of the trace, you might find this a bigger job than you think and now you have to ensure you keep track of 2 files.

Creating A IPv4 Filter With Your Packet Broker

One of the challenges I encounter when capturing packets is the sheer volume of data on todays networks. Most workstations have a minimum of 1 Gb connections and switch trunks are mostly 10 Gb connections.

This results in 2 issues:
- With a high packet rate and using a laptop or desktop to capture packets, you stand a chance of dropping packets.
- Going though gigabytes of data, is incredibly difficult and mostly unusable.

One way to mitigate these issues is to simply use a capture filter to reduce the amount of traffic captured. Unfortunately this technique doesn’t change the amount of packets being received by your capture device.