Whether it's in the midst of an incident, looking into an intermittent issue or a post event investigation to get to the bottom of a root cause, command line tools are the unsung heroes that come to our rescue again and again. In this talk, I'll go over the tools and techniques that helped me uncover insights during issues or incidents.
Some of these are:

"grep" through the logs when looking for failures within the timeframe of the issue at hand or ruling out a red herring
Seeing what's actually going over the wire, inside a process or heap with packet captures, thread dumps, heap dumps
The one question that we must ask during incidents: "What changed?"

I'll highlight each including its history of how it was born, its use and if and how we can contribute to its future.