macostcpprocessport

Find (and kill) processes listening to port 3000 on Mac

How do I manually find (and kill) process using the terminal that listen to/use my TCP ports? I'm on macOS.

Sometimes, after a crash or bug, my Rails app gets locked to port 3000, and I can't find it using ps -ef...

When running

rails server

I get

Address already in use - bind(2) (Errno::EADDRINUSE)

The same issue happens when stopping the Node.js process. Even after the process is stopped and the app stops running, port 3000 is locked. When starting the app again, getting

Address already in use (Errno::EADDRINUSE)
Solution

  • For macOS El Capitan and newer (or if your netstat doesn't support -p), use lsof:

    lsof -i tcp:3000

    Alternatively, you can use netstat:

    netstat -vanp tcp | grep 3000

    Once you have the PID (Process ID) use:

    kill -9 <PID>