Checking the status of Docker containers is an important starting point, when it comes to debugging container clusters. docker ps is an ideal tool to get you started. Unfortunately, the output can sometimes be quite verbose and overwhelming.
The --format parameter is supposed to ease the pain here, but Go templates can be quite tedious to write every time, too. To counter that a little, I reveal my favorite ready-to-alias docker ps calls in today’s post. I hope they make your everyday Docker life a little easier.
# Are my expected containers up?
docker ps --format "table {{.Names}}\t{{.Status}}"
# What ports do my containers expose?
docker ps --format "table {{.Names}}\t{{.Ports}}"
# What networks are my containers assigned to?
docker ps --format "table {{.Names}}\t{{.Networks}}"
All of them can be extended with more docker ps command line parameters, even when aliased later on.
As you may have noticed, my first column is always the container name followed by the property I’d like to analyse. This is my personal way to keep the output compact and focused on the problem at hand, but of course you can query any property you like. Check out the official documentation for a comprehensive list of available properties and pick what you need for the task.
Do you have a favourite formatting? Or do you want to talk about any other question? Feel free to let me know in the comments below. I plan to publish more cheat sheet-style posts in the future. This helps me out to share recent learnings in a focused way and provides you with quick help and valuable insights. You can find another example here, where I demonstrate how to set up Linux users with low maintenance work afterwards. Or if you are into Rust like I am, the Rust modules cheatsheet might be a valuable companion, when it comes to structuring your code with Rust Modules.
Until next time!
