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Node / Express: EADDRINUSE, Address already in use - how can I stop the process using the port?

I have a simple server running in node.js using connect:

var server = require('connect').createServer();
//actions...
server.listen(3000);

In my code I have actual route handlers, but that's the basic idea. The error I keep getting is:

EADDRINUSE, Address already in use

I receive this error when running my application again after it previously crashed or errors. Since I am not opening a new instance of terminal I close out the process with ctrl + z.

I am fairly certain all I have to do is close out the server or connection. I tried calling server.close() in process.on('exit', ...); with no luck.

Solution

  • process.on('exit', ..) isn't called if the process crashes or is killed. It is only called when the event loop ends, and since server.close() sort of ends the event loop (it still has to wait for currently running stacks here and there) it makes no sense to put that inside the exit event...

    On crash, do process.on('uncaughtException', ..) and on kill do process.on('SIGTERM', ..)

    That being said, SIGTERM (default kill signal) lets the app clean up, while SIGKILL (immediate termination) won't let the app do anything.