Strange "**** FAILED TO BIND TO PORT!" Error

[cblake18]

Hi gekigek99, I came across this script yesterday and was excited to see it was exactly what I was looking for with the server I'm currently hosting.

However, I'm having an issue when trying to join the server after launching the script. As soon as I attempt to connect, the error message:

"**** FAILED TO BIND TO PORT!
[00:23:44] [Server thread/WARN]: The exception was: io.netty.channel.unix.Errors$NativeIoException: bind(..) failed: Address already in use
[00:23:44] [Server thread/WARN]: Perhaps a server is already running on that port?"

comes up and stops the server immediately.

What I tryed:

I have made sure that no other instances of the server are running
I have made sure that nothing else is assigned to that port.
I have also tried using several different ports
I have edited the ports within the server.properties file as well as the python script.

What I noticed:

The server also runs flawlessly when I do not run it with the python script and there is no error message.

Any suggestions would be greatly appreciated. Thank you!

[gekigek99]

check that only one python script is running at a time.

use this command to check what port are being used with this:
netstat -tulpn | grep LISTEN
you should find a what program is using that port that the python script is trying to bind to.

update me on your findings

[cblake18]

Thanks for the reply man. It turns out I shoulda just done a little research on the difference between the listener and target port.

I had them set as the same thing (25565) which obviously caused me to get the “failed to bind to port” error.
Once I changed them and set the listener and target IP to my local IP, the script worked great.

Maybe someone else can learn from my stupid mistake lol. Thanks again.

[gekigek99]

no worries!
good that you solved the problem!
(I hate this very silly problems that end up wasting your entire day ahahah)
I modified your question so that it's easyer to look up also for other people