In your case it was some other process that was using the port and as indicated in the comments, sudo netstat -pna | grep 3000
helped you in solving the problem.
While in other cases (I myself encountered it many times) it mostly is the same container running at some other instance. In that case docker ps
was very helpful as often I left the same containers running in other directories and then tried running again at other places, where same container names were used.
How docker ps
helped me: docker rm -f $(docker ps -aq)
is a short command which I use to remove all containers.
Edit: Added how docker ps
helped me.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…