Challenge, Easy,  on  Linux, Networking

Classic Sysadmin Task: Which Process Is Listening on a Port?

You have access to a Linux server running multiple services. Your challenge is to identify which process is listening on port 12345. This task is simple, but be careful - you only have one attempt to submit the correct answer.

Good luck!

Hint 1

There are plenty of tools to list ports and their associated processes: netstat, ss, lsof, etc. Pick one and try to figure out how to use it for this particular task.

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How to Author Challenges on iximiuz Labs

Instead of providing a subpar online editing experience, iximiuz Labs offers a helper CLI tool called labctl, allowing you to use your favorite text editor (or a full-featured IDE) to write content from the comfort of your local machine.

Install labctl CLI

curl -sf https://labs.iximiuz.com/cli/install.sh | sh

This will download and install the latest version of the labctl CLI. You only need to do this once per workstation.

Authorize labctl

labctl auth login

This will open a browser window asking you to authorize labctl to access your account. You need to do it after a fresh install of labctl and repeat it whenever the auth session expires.

Pull challenge content

labctl content pull challenge linux-find-process-using-port

This will create a local copy of the challenge content in a directory named linux-find-process-using-port. You only need to do this once per challenge.

Stream your changes

labctl content push -fw challenge linux-find-process-using-port

Run this command in a separate terminal to continuously upload your changes to the server while editing the challenge in your favorite text editor or IDE.

You can also use labctl to create, list, and delete your content. Learn more about the available commands: labctl content --help

Start challenge