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Ruby Build a Todo List Application with Rails 4 Build a Todo List Application with Rails 4 Generate a Scaffold

Kern Tallett
Kern Tallett
10,012 Points
Posted by Kern Tallett
Kern Tallett
10,012 Points

I am getting an error message when i try to start the rails server

/Users/Kern/.rbenv/versions/2.1.0/lib/ruby/2.1.0/socket.rb:206:in `bind': Address already in use - bind(2) for 0.0.0.0:3000 (Errno::EADDRINUSE)

Any ideas what is going on?

4 Answers

Scott Magdalein
Scott Magdalein
1,667 Points
Scott Magdalein
Scott Magdalein
1,667 Points

To see what's running on port 3000, type the following into the terminal: lsof -i tcp:3000

It should show you the open file or process on that port. To kill that process (so you can free up port 3000 for your Rails server), copy the PID number and then type this into your terminal: kill -QUIT <PID> (remember to replace <PID> with the number you copied before)

Now port 3000 should be open for your Rails server. Alternatively, you could specific the port Karl Coelho stated above.

Sergio Barrera
Sergio Barrera
4,198 Points
Sergio Barrera
Sergio Barrera
4,198 Points

Hi Kern, I think you're trying to start up another server instance on the webrick server. Check your terminal window(s) and see if there is a localhost:300 server already running for the same project/rails app.

karlcoelho
karlcoelho
1,361 Points
karlcoelho
karlcoelho
1,361 Points

Either run the start on another port, by

rails s -p 4000

or restart Terminal. If that doesn't work. Restart the computer.

Kern Tallett
Kern Tallett
10,012 Points
Kern Tallett
Kern Tallett
10,012 Points

Thanks guys both were correct in the sense as the first was the reason and the second was what i should do. I just forget sometimes restarting the computer can really help. I am unsure if i can give best answer to both. I am guessing not as it simply would be against the spirit of it but thanks both of you.