Error listen eaddrinuse address already in use 3000 ubuntu

If I run a server with the port 80, and I try to use XMLHttpRequest I am getting this error: Error: listen EADDRINUSE Why is it problem for NodeJS, if I want to do a request, while I run a server o...

The aforementioned killall -9 node, suggested by Patrick works as expected and solves the problem but you may want to read the edit part of this very answer about why kill -9 may not be the best way to do it.

On top of that you might want to target a single process rather than blindly killing all active processes.

In that case, first get the process ID (PID) of the process running on that port (say 8888):

lsof -i tcp:8888

This will return something like:

COMMAND   PID    USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
node     57385   You   11u  IPv6 0xac745b2749fd2be3      0t0  TCP *:ddi-tcp-1 (LISTEN)

Then just do (ps — actually do not. Please keep reading below):

kill -9 57385

You can read a bit more about this here.

EDIT: I was reading on a fairly related topic today and stumbled upon this interesting thread on why should i not kill -9 a process.

Generally, you should use kill -15 before kill -9 to give the target process a chance to clean up after itself. (Processes can’t catch or ignore SIGKILL, but they can and often do catch SIGTERM.) If you don’t give the process a chance to finish what it’s doing and clean up, it may leave corrupted files (or other state) around that it won’t be able to understand once restarted.

So, as stated you should better kill the above process with:

kill -15 57385

EDIT 2: As noted in a comment around here many times this error is a consequence of not exiting a process gracefully. That means, a lot of people exit a node command (or any other) using CTRL+Z. The correct way of stopping a running process is issuing the CTRL+C command which performs a clean exit.

Exiting a process the right way will free up that port while shutting down. This will allow you to restart the process without going through the trouble of killing it yourself before being able to re-run it again.

This quick article shows you how to solve a common error you might confront when working with Node.js.

The Problem

When developing a Node.js application (with Express.js), I sometimes fall into the following problem:

Error: listen EADDRINUSE: address already in use :::3000

Full error message:

Error: listen EADDRINUSE: address already in use :::3000
    at Server.setupListenHandle [as _listen2] (node:net:1380:16)
    at listenInCluster (node:net:1428:12)
    at Server.listen (node:net:1516:7)
    at Function.listen (/Users/goodman/Desktop/Projects/kindacode/api/node_modules/express/lib/application.js:635:24)
    at server (/Users/goodman/Desktop/Projects/kindacode/api/src/index.ts:60:7)
    at bootstrap (/Users/goodman/Desktop/Projects/kindacode/api/src/index.ts:73:3)
    at processTicksAndRejections (node:internal/process/task_queues:96:5) {
  code: 'EADDRINUSE',
  errno: -48,
  syscall: 'listen',
  address: '::',
  port: 3000
}

The console message indicates that I am trying to run my app with a port being used by some program. This happens after my app crashes. Behind the scene, it’s very likely that there is a terminal window hiding out in the background that is still running the app. If you encounter the same problem as mine, don’t panic. Below is the solution.

The Solution

What we have to do is really simple: kill the process that is running on the port. Execute the command below:

npx kill-port 3000

If you need to free a port other than 3000, run the command above on that port. It’s also possible to terminate multiple ports at once:

npx kill-port 3000 4000 5000 6000 7000

Another solution that can solve this problem, as well as many others, is just restarting your computer (you even don’t have to do that in this situation).

That’s it. Further reading:

  • Node.js: Turn a Relative Path into an Absolute Path
  • Nodemon: Automatically Restart a Node.js App on Crash
  • 2 Ways to Set Default Time Zone in Node.js
  • 7 Best Open-Source HTTP Request Libraries for Node.js
  • Node.js: Use Async Imports (Dynamic Imports) with ES Modules

You can also check out our Node.js category page for the latest tutorials and examples.

Cover image for Fixing nodemon 'Error: listen EADDRINUSE: address in use'

Matt Heindel

Matt Heindel

Posted on Jul 8, 2021

• Updated on Jul 12, 2021

Has this ever happened to you?

You go to start up your server with npm start and you get the below error message

$ npm start

> cruddy-todos@1.0.0 start /home/mc_heindel/HackReactor/hr-rfp54-cruddy-todo
> npx nodemon ./server.js

[nodemon] 2.0.6
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: js,mjs,json
[nodemon] starting `node ./server.js`
events.js:292
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE: address already in use :::3000
    at Server.setupListenHandle [as _listen2] (net.js:1318:16)
    at listenInCluster (net.js:1366:12)
    at Server.listen (net.js:1452:7)
    at Function.listen (/home/mc_heindel/HackReactor/hr-rfp54-cruddy-todo/node_modules/express/lib/application.js:618:24)
    at Object.<anonymous> (/home/mc_heindel/HackReactor/hr-rfp54-cruddy-todo/server.js:79:5)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)
    at internal/main/run_main_module.js:17:47
Emitted 'error' event on Server instance at:
    at emitErrorNT (net.js:1345:8)
    at processTicksAndRejections (internal/process/task_queues.js:80:21) {
  code: 'EADDRINUSE',
  errno: -98,
  syscall: 'listen',
  address: '::',
  port: 3000
}
[nodemon] app crashed - waiting for file changes before starting...

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Exit fullscreen mode

Luckily there is a solution!

This error occurs when a process is already running on the port you’re trying to use. All you need to do is kill that process. In this case, since the port we want to use is 3000 we could simply paste and execute the below code in our terminal.

kill -9 $(lsof -t -i:3000)

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Exit fullscreen mode

This will kill the process running on port 3000 and you should be good to start your server with npm start like usual.

Save this command for future use

If this happens often, it’s a great idea to add an alias to bash for reuse anytime. The below code is a function that accepts a port number to kill and when saved can be reused for any port number.

killport() { kill -9 $(lsof -t -i:"$@"); } # kill process on specified port number

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Exit fullscreen mode

The quick and easy way to save

Simply execute the below command and the killport function will be available every time you open bash. Just remember to restart your terminal for the saved function to be loaded after first adding it.

echo 'killport() { kill -9 $(lsof -t -i:"$@"); } # kill process on specified port number' >> ~/.bashrc

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Exit fullscreen mode

Below is an example of how the newly defined killport function can be used to kill a process on port 3000.

killport 3000

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Exit fullscreen mode

The slightly more advanced way to save

To save this function alongside your other bash aliases and configurations you just need to add the below code to ~/.bashrc or ~/.bash_aliases which can be accomplished using vim ~/.bashrc and pasting in the code snippet.

killport() { kill -9 $(lsof -t -i:"$@"); } # kill process on specified port number

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Closed

ctfrancia opened this issue

Mar 27, 2019

· 42 comments

Comments

@ctfrancia

Hey guys, so I have been just trying to start testing my Koa server using Supertest.

I am getting the error: Error: listen EADDRINUSE: address already in use :::3000

I have tried closing everything down on that port and run it but I’m still getting the issue.

Here is my app:

require('dotenv').config();
const Koa = require('koa');
const app = new Koa();
const router = require('./router');
const PORT = process.env.NODE_PORT || 3001;
const ENV = process.env.NODE_ENV || 'Development';
const logger = require('koa-logger');

app.use(logger());
app.use(router.routes());

app.listen(PORT, (err) => {
    if (err) console.error('❌ Unable to connect the server: ', err);
    console.log(`🌍 Server listening on port ${PORT} - ${ENV} environment`);
  });

    module.exports = app;

my router:

const Router = require('koa-router');
const router = new Router();

router.get('/', ctx => ctx.body = 'Sending some JSON');
  module.exports = router;

finally the test:

const server = require('../index');
const request = require('supertest').agent(server.listen());

afterEach(() => {
  server.close();
});

describe('routes: index', ()=> {
  it('should reach endpoint', async () => {
    const response = await request(server).get('/');
   
    expect(response.status).toEqual(200);
    expect(response.body).toEqual('Sending some JSON');
  });
});

my server isn’t even running on port 3000 it is running on 8080
however, just to make sure I will run my server on 3000 and it starts up no problem. I then try to run the test, I get the error again with the server running on 3000 and the server not. Kinda stuck

@rimiti

Could you send us the output of:
lsof -i:3000

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@ctfrancia

@ctfrancia

UPDATE so the reason was because in my app.test.js file I had a series of tests that were not closing after completion because I was running tests like:

const app = require('../index');

describe('server working', () => {
  
  it('should exist', async (done)=> {
    expect(app).toBeDefined();
    done();
  });

  it('should be an object', async (done)=>{
    expect(typeof app).toBe("object");
    done();
  });
});

and I am still getting the error:

Jest did not exit one second after the test run has completed.

This usually means that there are asynchronous operations that weren’t stopped in your tests. Consider running Jest with --detectOpenHandles to troubleshoot this issue.

@aech12

I had that exact error message, try this out:

Expected: I can use app.listen(PORT, ()=>{})

Code: index.js exports «app», app.listen(PORT, ()=>{}) is uncommented

Output: npm test => «Jest did not exit one second after the test run has completed.
This usually means that there are asynchronous operations that weren’t stopped in your tests. Consider running Jest with --detectOpenHandles to troubleshoot this issue.»

Workaround: comment/delete app.listen(PORT) and listen to the port on another file (example: require «app» from index.js in app.js and listen to a port in app.js)

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@aech12

what’s weird is that the documentation claims «if the server is not already listening for connections then it is bound to an ephemeral port for you so there is no need to keep track of ports.»

@ctfrancia

Ok thanks a lot, I will be checking that out for sure!

@dgreene1

Looks like you have to do two things:

  1. ensure that the app has not yet been started (i.e. put the app.listen in an if statement that asserts it’s not in test mode first)
  2. pass koa.callback() into supertest as follows:

@dionisoros

lsof -i:3000 
kill -9 [PID] 
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@Atabic

You are actually running the main server in the terminal. Stop the server so the debugger can run on the same PORT

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@spock123

So I had this issue as well.
What you want to do is that you don’t want to start your server. In your main server express file you should export the server. But do NOT call the listen method.

So modify your code so that when you’re testing (for example by setting an environment variable and looking for that), you’re not calling the listen() method. This should resolve it and let you run your tests in parallel.

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@avencat

@Robertosousa86

Cheers from brazil, thank you all for the support!

@HashemDeveloper

lsof -i:3000 
kill -9 [PID] 

What is PID here? New comer please help. Thank you.

@cguidog

@HashemDeveloper when you run lsof -i:3000, you will get some information related to the port. the second column in the returned table says PID, that’s what you have to type instead of [PID] when run kill -9

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@HashemDeveloper

@HashemDeveloper when you run lsof -i:3000, you will get some information related to the port. the second column in the returned table says PID, that’s what you have to type instead of [PID] when run kill -9

I actually figured that out by try and error. Thank you for the reply though.

@Abdelrahmanyassin786

im new to web development and i get the same error and dont know exactly what to do can someone please dumb it down for me

@cguidog

@Abdelrahmanyassin786 In your terminal window, where you are running your application; run this command:
lsof -i:3000
It will return some information related to process running; look for the PID number.
next, run kill -9 [PID], but replace [PID] with the PID number from the first command.
That will kill the process completely, and you will be able to start it again.

@Abdelrahmanyassin786

it tells me 1sof command is not found

@Abdelrahmanyassin786

the thing is that my root route doesnt work but if i type for example /blog/new it opens fine

@cguidog

@Abdelrahmanyassin786

still doesnt work
i wish i would know how to copy my terminal in here like you guys do so i could show you

@Abdelrahmanyassin786

i tried sth i typed killall -9
then i did killall -u
then killall -v it worked but i honestly dont know which made it work

@JoeyHayfron

So I had this issue as well.
What you want to do is that you don’t want to start your server. In your main server express file you should export the server. But do NOT call the listen method.

So modify your code so that when you’re testing (for example by setting an environment variable and looking for that), you’re not calling the listen() method. This should resolve it and let you run your tests in parallel.

@spock123 please do you mean exporting the what i assign the express function to?
For instance
i have
const app = express();

const port = process.env.PORT || 3000;
const server = app.listen(port, () => { console.log(Listening on ${port}.....) });

module.exports = server;

Please do you mean i should export just app??

@MiraTechCoder

Hey guys, so I have been just trying to start testing my Koa server using Supertest.

I am getting the error: Error: listen EADDRINUSE: address already in use :::3000

I have tried closing everything down on that port and run it but I’m still getting the issue.

Here is my app:

require('dotenv').config();
const Koa = require('koa');
const app = new Koa();
const router = require('./router');
const PORT = process.env.NODE_PORT || 3001;
const ENV = process.env.NODE_ENV || 'Development';
const logger = require('koa-logger');

app.use(logger());
app.use(router.routes());

app.listen(PORT, (err) => {
    if (err) console.error('❌ Unable to connect the server: ', err);
    console.log(`🌍 Server listening on port ${PORT} - ${ENV} environment`);
  });

    module.exports = app;

my router:

const Router = require('koa-router');
const router = new Router();

router.get('/', ctx => ctx.body = 'Sending some JSON');
  module.exports = router;

finally the test:

const server = require('../index');
const request = require('supertest').agent(server.listen());

afterEach(() => {
  server.close();
});

describe('routes: index', ()=> {
  it('should reach endpoint', async () => {
    const response = await request(server).get('/');
   
    expect(response.status).toEqual(200);
    expect(response.body).toEqual('Sending some JSON');
  });
});

my server isn’t even running on port 3000 it is running on 8080
however, just to make sure I will run my server on 3000 and it starts up no problem. I then try to run the test, I get the error again with the server running on 3000 and the server not. Kinda stuck

i experience these problem
root of these problem :
is when i try to run my previous project i created and then i open the server(mix phx.server)
after i run and tried i just close the terminal(MINGW64/MSYS2 terminal) with out killing the running the server(which i don’t know how to do it)
after these i create another project and running the server (mix phx.server)
then these problem occurs also in me

my solution to these: i restart my computer and run again then i find it running good again.

but my problem (how to kill the server with out restarting it)

@DrobyshevAlex

Sometimes, when i press save and the server restarts i get the same error.

@abdennourzahaf

I have the same problem and i couldn’t understand what do @spock123 and @aech12 mean by exporting the server.
How can you export the server if you are not calling the listen() method, which returns the server object at the first place?
I am really confused, if you can provide a code snippet it would help.
NOTE: I am using —runInBand flag for the moment, it works but it slows down the testing.

@spock123

module.exports = server;

Please do you mean i should export just app??

Yes! precisely!
You export just the app, but do not call listen()

@spock123

I have the same problem and i couldn’t understand what do @spock123 and @aech12 mean by exporting the server.
How can you export the server if you are not calling the listen() method, which returns the server object at the first place?
I am really confused, if you can provide a code snippet it would help.
NOTE: I am using —runInBand flag for the moment, it works but it slows down the testing.

Hi @zfnori
The server is an instantiation of your application. But only when you call the «listen» method, will it start listening for incoming request.

This means you can export that «server» object like any other variable.
Hope it makes sense.

@JoeyHayfron

@nirav7707

I had that exact error message, try this out:

Expected: I can use app.listen(PORT, ()=>{})

Code: index.js exports «app», app.listen(PORT, ()=>{}) is uncommented

Output: npm test => «Jest did not exit one second after the test run has completed.
This usually means that there are asynchronous operations that weren’t stopped in your tests. Consider running Jest with --detectOpenHandles to troubleshoot this issue.»

Workaround: comment/delete app.listen(PORT) and listen to the port on another file (example: require «app» from index.js in app.js and listen to a port in app.js)

thankyou @aech12 your solution work for me

@MaciejKutynia

I have the same issue, solution that I found is go to node_modules find nodemon/monitor/run. And there is variable «killedAfterChange» in my case var killedAfterChange = false; i changed to var killedAfterChange = true; and it’s worked fine

@alforsii

Hi everyon. I had this error:
Error: listen EADDRINUSE: address already in use 3001
The same as above. The problem was in my case colors npm package. I did attach color to the PORT before I passed to the app.listen, like :
const PORT = process.env.PORT.yellow || 5000;
Don’t do this,instead use color extension in the console.log, like:
app.listen(PORT, () =>
console.log(
Server running in ${process.env.NODE_ENV.yellow} mode on port ${PORT.yellow}
)
);
Something like this. Hopefully, it helps someone. My issue was solved with this. Happy coding guys! 🙌

@GregPetropoulos

I added an additional node and started the server on it and ran with out issues. I am guessing you cant run concurrently dev dependencies on the main node. Not sure why this worked but basically just click the plus sign on your vs code in the terminal to open a secondary node and run the app.

@GregPetropoulos

Never mind that didn’t hold up after rerunning the app. I found that my insomnia running on the same port as my app is conflicting as I check my routes

@chinedu360

You are actually running the main server in the terminal. Stop the server so the debugger can run on the same PORT

simple yet very effective answer.

@vasilisliapis

I had the same problem and instead of writing
afterEach(() => {
server.close();
});
I wrote
afterEach(async() => {
await server.close();
});
because server.close() returns a promise

@emercadogarcia

lsof -i:3000 
kill -9 [PID] 

this is solution; tanks.

@hzlnqodrey

lsof -i:3000 
kill -9 [PID] 

This worked for me. Thanks a lot.

@vladyslav-dev

I had the same problem and the problem was that I wrote app.listen() two times ))))

@korovenko-tatyana

Perhaps you have 2 projects and one with docker. Check «docker ps» — maybe you use this port. Then stop it.

@Dharmesh1981

I had the same problem and just restart VS Code and the problem solved

@AlbertVilaCalvo

Error: listen EADDRINUSE: address already in use :::3000
at Server.setupListenHandle [as _listen2] (net.js:1280:14)
at listenInCluster (net.js:1328:12)
at Server.listen (net.js:1415:7)

asked Sep 9, 2020 at 18:09

Nikhil Sharma's user avatar

2

Use fuser 3000/tcp to get the pid of the process running on that port.
After that run ls -l /proc/<PID>/exe to get some process details.
Use it’s output to determine whether you want to kill that process or start your service on a different port ( imo I would recommend the 2nd option).

answered Sep 9, 2020 at 20:11

charbel k's user avatar

1

If you have installed nodejs in your system,
Open terminal and type the following command to kill the process on a port

Syntax: npx kill-port <port-number>

Example

npx kill-port 3000

answered Dec 9, 2022 at 9:53

Codemaker's user avatar

In this tutorial, we are going to learn about how to solve the Error: listen EADDRINUSE: address already in use in Node.js.

When we run a development server of react or other apps, sometimes we will see the following error in our terminal.

Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
    at Server.setupListenHandle [as _listen2] (net.js:1306:16)
    at listenInCluster (net.js:1354:12)
    at GetAddrInfoReqWrap.doListen [as callback] (net.js:1493:7)
    at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:65:10)
Emitted 'error' event on Server instance at:
    at emitErrorNT (net.js:1333:8)
    at processTicksAndRejections (internal/process/task_queues.js:81:21) {
  code: 'EADDRINUSE',
  errno: 'EADDRINUSE',
  syscall: 'listen',
  address: '127.0.0.1',
  port: 3000
}

This error tells us, the port number we are trying to run a server is already in use.

To solve this error, we need to close the program that is using this port or try to use a different port.

If you don’t know, which program is using that port then you can use the following command to kill the all node processes currently running.

Fixing nodemon ‘Error: listen EADDRINUSE: address in use’

Has this ever happened to you?

You go to start up your server with npm start and you get the below error message

Exit fullscreen mode

Luckily there is a solution!

This error occurs when a process is already running on the port you’re trying to use. All you need to do is kill that process. In this case, since the port we want to use is 3000 we could simply paste and execute the below code in our terminal.

Exit fullscreen mode

This will kill the process running on port 3000 and you should be good to start your server with npm start like usual.

Save this command for future use

If this happens often, it’s a great idea to add an alias to bash for reuse anytime. The below code is a function that accepts a port number to kill and when saved can be reused for any port number.

Exit fullscreen mode

The quick and easy way to save

Simply execute the below command and the killport function will be available every time you open bash. Just remember to restart your terminal for the saved function to be loaded after first adding it.

Exit fullscreen mode

Below is an example of how the newly defined killport function can be used to kill a process on port 3000.

Exit fullscreen mode

The slightly more advanced way to save

To save this function alongside your other bash aliases and configurations you just need to add the below code to

/.bash_aliases which can be accomplished using vim

/.bashrc and pasting in the code snippet.

Exit fullscreen mode

Top comments (3)

The wait is over! Killer post.

We ran into this yesterday and had to hunt down the process that was running. We’ll use this next time. It’ll be a time saver for sure.

Glad I could help spare you some headache!

If you’re using ts-node with npx, I was having the same issue. I installed nodemon and ts-node as dev dependencies then removed npx and don’t have the problem anymore.

For further actions, you may consider blocking this person and/or reporting abuse

Timeless DEV post.

Git Concepts I Wish I Knew Years Ago

The most used technology by developers is not Javascript.

It’s not Python or HTML.

It hardly even gets mentioned in interviews or listed as a pre-requisite for jobs.

I’m talking about Git and version control of course.

Источник

How to kill server when seeing “EADDRINUSE: address already in use”

A tutorial on how to kill the process manually when “EADDRINUSE” happens on Mac/Linux and Windows.

The Problem

When trying to restart a Node application, the previous one did not shut down properly, and you may see a “ listen EADDRINUSE: address already in use” error such as:

The cause behind this issue

The reason behind this is that

process.on(‘exit’, . ) isn’t called when 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.

Solution

The proper fix for the application would be

  • On crash, do process.on(‘uncaughtException’, ..)
  • And on kill do process.on(‘SIGTERM’, ..)

When this EADDRINUSE issue has already happened, in order to resolve it, you need to kill the process manually. In order to do that, you need to find the process id (PID) of the process. You know the process is occupying a particular port on your machine or server.

Kill the process manually

For Mac/Linux

To find the process id (PID) associated with the port

Then to kill the process

Use -9 option to make sure the process dies immediately

If you get permissions errors, you may need to use the sudo keyword, for example:

For Windows

Solution 1: Task Manager

Open the Task Manager application ( taskman.exe), from either the Processes or Services tab sort by the PID column. To display the PID column, right-click the header row and select PID from the list. Right-click the process you want to stop and select End task.

Solution 2: Use Command prompt

Open a CMD window in Administrator mode by navigating to Start > Run > type cmd > right-click Command Prompt, then select Run as administrator.

Use the netstat command lists all the active ports. The -a switch displays all ports in use, not just the ports associated with the current user. The -n option stops a hostname lookup (which takes a long time). The -o option lists the process ID that is responsible for the port activity. The findstr command matches the header row that contains the PID string, and the port you are looking for, in a port format with the preceding colon, is :3000.

To kill this process (the /f is force):

Enjoy!

And that’s about it. Thanks for reading

Level Up Coding

Thanks for being a part of our community! Level Up is transforming tech recruiting. Find your perfect job at the best companies.

Источник

[nodemon] Error: listen EADDRINUSE: address already in use #676

Comments

I’m running into an error in nodemon today, which only happens with esm using -r from the CLI. Here’s a dead-simple reproduction:

When I run yarn dev from the terminal, and then do Ctrl+S in app.js in the editor, I get

You can see that the app boots correctly, but as soon as any file changes, nodemon can’t restart it. In the meantime, the app still continues to run in the background. If I do Ctrl+C , it quits, but there’s no more process on port 3000 , so killing it by port fuser -k 3000/tcp doesn’t do anything.

  • it works without esm , i.e. if I change «dev»: «nodemon -r esm app» to «dev»: «nodemon app» , the error goes away, and nodemon restarts correctly
  • it works with esm using require(«esm»)(module) syntax instead of -r
  • it works either way without express or any web server (because the port is not used)
  • same issue on Node 11.2.0 , 11.1.0 , and 10.13.0

Tried rebooting, reinstalling Node, removing yarn.lock , then removing and re-installing node_modules , locking to older versions of esm , nodemon , and express . I’m out of options here.

At first, I thought this was nodemon ‘s fault, so I scavenged many threads with this error, but to no avail. Then I noticed that the error appears to be emitted from esm , so I thought I’d post here. Sorry, if I’m posting in a wrong repo; it seems the culprit lies in this library. Any clues are appreciated!

  • OS: Ubuntu 18.10 cosmic
  • Node: 11.2.0 (other versions too, see above)
  • npm: 6.4.1
  • yarn: 1.12.3

The text was updated successfully, but these errors were encountered:

Источник

Error: listen EADDRINUSE: address already in use . 5000 #1849

Comments

  • nodemon -v : 2.0.7
  • node -v : 14.16.01
  • Operating system/terminal environment: MacOS Big Sur
  • Using Docker? No
  • Command you ran: nodemon server

Expected behaviour

Close port before reinitializing server.

Actual behaviour

Steps to reproduce

  1. Initialize app (basic MERN app)
  2. Save any file.
  3. Error is thrown.

This only started happening after I updated my Mac to Big Sur. I can circumvent this issue by either stopping the app and killing the port or by saving a second time a couple of seconds after the first crashed the server.

The text was updated successfully, but these errors were encountered:

Can you explain and provide example code? Because I’m pretty sure «basic» actually means: set up mongodb, add nginx, possibly webpack and a bunch others. i.e. not compatible with «basic».

If you can provide code that replicates this issue, happy to look at it. Otherwise this is too vague.

server.js roughly looks like this:

Okay, start striping the code back until you have the bare minimum and you can still replicate, then post that here, then we can take a look.

I’ve recently started facing the same issue on my own application. Nodemon was working fine all this while but now seems to be leaving a single Node process listening on an open port (3000, in my case). I looked up past issues on the GitHub repo and found that the most popular one had been closed last year.

My stripped-down entry file (app.js) looks like this:

As for other environment and version info:

  • Node.js: v15.14.0
  • Nodemon: 2.0.7
  • Express: 4.17.1
  • OS: Ubuntu 20.04.2 LTS on Windows 10 (WSL 2)

Right now, I’m forced to manually kill the running process myself and restart the Node server, which defeats the purpose of using Nodemon at all. Any help is appreciated.

I’ve found a temporary work-around, the steps for which are listed below:

  1. Install the NPM kill-port package as a development dependency: npm install -D kill-port
  2. Create a new file in your project’s root directory called nodemon.json and paste in the following JSON (edit the port numbers below from 3000 to whatever port you’re using for your Node.js app):
  1. Add the following NPM script to your package.json file (if you haven’t already):

All credit goes to Tudor Constantin on Stack Overflow. However, it is a bit tedious and definitely a workaround, not something that should be done for all future Node.js projects.

Correction: The method I’ve shown above provides inconsistent results, and shouldn’t be considered a fix. It only works half of the time, and also occasionally crashes when Nodemon restarts.

Back to the drawing board.

I came across variants of this issue many times without ever being able to replicate it deterministically. But on all cases, I have found that.

  • Killing the port-process $ on the nodemon events start , restart or crash , does not solve my problem.
  • Synchronously killing it right before calling .listen(. ) on my express app does not solve my problem.
  • However, asynchronously killing it before calling .listen(. ) in a .then() does solve my problem, when.
    • . either fuser -k $/tcp and npx kill-port $ is used to kill the port-process.
    • . the nodemon restart is delayed (hint: to delay it, merge your current nodemon.json with > ). I have the solution below running almost all of the times with .

I have written a brief code snippet that does the job of killing the conflicting port-process at run-time, using fuser . I don’t think adapting the code so as to use npx kill-port $ would be very hard: I would appreciate if anyone could augment my code with that adaptation 🙂

Basically, one call of killPort keeps killing all the port-processes that hold onto the port $ until no processes are left. Finally, an interval is set so that if a round of killPort has killed any process, it checks again after some time. This killing and re-killing was done because for some reason the conflicting port-processes would get killed once but the error EADDRINUSE would still show up. It may be overkill, pun intended, but to be honest, it works, and I’m happy because of that.

Here it is, along with my current use case and its output:

Источник

Node/Экспресс: EADDRINUSE, адрес уже используется — Kill server

У меня есть простой сервер, работающий в node.js, используя connect:

В моем коде у меня есть фактические обработчики, но это основная идея. Проблема, которую я получаю, —

Я получаю эту ошибку при повторном запуске приложения после того, как он был ранее разбит или ошибки. Поскольку я не открываю новый экземпляр терминала, я закрываю процесс с помощью ctr + z .

Я уверен, что все, что мне нужно сделать, это закрыть сервер или соединение. Я пробовал звонить server.close() в process.on(‘exit’, . ); без везения.

ОТВЕТЫ

Ответ 1

process.on(‘exit’, ..) не вызывается, если процесс вылетает или уничтожается. Он вызывается только тогда, когда цикл события заканчивается, и поскольку server.close() завершает цикл события (он все еще должен ждать текущих стеков здесь и там), нет смысла помещать это внутри события exit.

В случае сбоя, сделайте process.on(‘uncaughtException’, ..) и на kill do process.on(‘SIGTERM’, ..)

При этом SIGTERM (сигнал об отключении по умолчанию) позволяет очищать приложение, а SIGKILL (немедленное завершение) не позволит приложению ничего делать.

Ответ 2

Вы также можете перейти по маршруту командной строки:

чтобы получить идентификаторы процесса.

Выполнение -9 на kill отправляет SIGKILL (вместо SIGTERM). SIGTERM для меня иногда игнорировался node.

Ответ 3

Я нашел для меня самый быстрый способ разрешить это:

Ответ 4

Я ударил это на своем ноутбуке, работающем с win8. это сработало.

Запустите cmd.exe как «Администратор»:

Ответ 5

Сначала вы хотели бы знать, какой процесс использует port 3000

в этом списке будет отображаться все PID, прослушивающие этот порт, как только у вас есть PID, вы можете его завершить следующим образом:

Ответ 6

Проверьте идентификатор PID, то есть идентификатор процесса, запущенного на порту 3000, с помощью команды ниже:

Он выводит что-то вроде следующего:

Теперь убейте процесс, используя:

Ответ 7

Я нашел это решение, попробуйте дать разрешение на использование sudo

Ответ 8

Linux

Запустите ps и определите PID вашего процесса узла.

Затем запустите sudo kill PID

Windows

Используйте список задач для отображения списка запущенных процессов:

Затем завершите процесс узла следующим образом (используя PID, полученный из команды tasklist ):

Ответ 9

Я получал эту ошибку один раз и использовал многие из этих подходов.

Мои проблемы состояли в том, что у меня было два вызова app.listen(3000); в том же app.js script. Первый app.listen() преуспел там, где второй сбросил ошибку.

Еще одна полезная команда, с которой я столкнулся, помогла мне отладить sudo fuser -k 3000/tcp , которая убьет любые запущенные процессы, которые вы могли бы запустить (некоторые процессы могут перезагружаться, например, если они запускаются с forever.js, но это было полезно для меня).

Ответ 10

Вот один вкладыш (замените 3000 на порт или переменную конфигурации):

Ответ 11

Для окон откройте диспетчер задач и найдите процессы node.exe. Убейте их всех с помощью End Task.

Ответ 12

FYI, вы можете убить процесс в одной команде sudo fuser -k 3000/tcp . Это можно сделать для всех других портов, таких как 8000, 8080 или 9000, которые обычно используются для разработки.

Ответ 13

Ответ 14

если вы используете Mac или Linux, вы можете попробовать эту команду на терминале

Ответ 15

Сначала узнайте, что работает, используя:

Вы получите что-то вроде:

Затем вы можете убить процесс следующим образом:

Тогда вы сможете работать без ошибок EADDRINUSE: 3000 listen

Ответ 16

Диспетчер задач (ctrl + alt + del) →

выберите «node.exe» и нажмите «Завершить процесс»

Ответ 17

Для Visual Studio Noobs, как я

Возможно, вы запускаете процесс в других терминалах!

После закрытия терминала в Visual Studio терминал просто исчезает.

Я вручную создал новый, думая, что предыдущий был уничтожен. В действительности, каждый раз, когда я нажимал на Новый терминал, я фактически создавал новый поверх предыдущих.

Итак, я нашел первый терминал и. Вуаля, я работал там на сервере.

Ответ 18

Вы можете использовать hot- node, чтобы предотвратить ошибки сервера/ошибки времени выполнения. Горячая node автоматически перезапускает приложение nodejs для вас всякий раз, когда происходит изменение в программе node [источник]/процесс [запуск node program].

Установите hot- node с помощью npm, используя глобальную опцию:

Ответ 19

  1. ps предоставит статус процесса, aux предоставит список: все процессы пользователя, u: процессы пользователя, x: все остальные процессы, не подключенные к терминалу.
  2. символ pipes: | передаст результат ps aux для дальнейшей манипуляции.
  3. grep будет искать предоставленную строку (в нашем случае это узел) из списка, предоставленного ps aux.

Ответ 20

При должном уважении ко всем ответам в форме я хотел бы добавить точку.

Я обнаружил, что когда я заканчиваю приложение node при ошибке с помощью Ctrl + Z, то в следующий раз, когда я пытаюсь открыть его, вы получаете ту же ошибку EADDRINUSE.

Когда я использую Ctrl + C для завершения приложения node, в следующий раз, когда я его открыл, он сделал это без сучка и задоринки.

Изменение номера порта на что-то другое, кроме ошибки, вызвало проблему.

Ответ 21

На всякий случай проверьте, добавили ли вы эту строку несколько по ошибке

Вышеприведенный код предназначен для экспресс-проверки, но просто проверьте, пытаетесь ли вы дважды использовать один и тот же порт в своем коде.

Ответ 22

Добавить функцию в

Измените изменения: source

И используйте его: killTcpListen 3000

Ответ 23

Win10, git bash v2.15, node v8.9.1, npm v5.5.1

У меня был пакет package.json script, чтобы запустить node: «start»: «node index.js»

Всякий раз, когда я использовал это, независимо от того, убил ли я его с помощью ctrl + c, я столкнулся с этой проблемой.

Если я просто запустил node index.js из git bash вместо npm run start и убил ctrl + c, я никогда не получал эту ошибку.

Я не уверен, почему, но я решил, что это может помочь кому-то.

Ответ 24

Node работает где-то в памяти и заблокирован этот порт. В Windows эта проблема, как и большинство проблем Windows, будет решена путем нажатия CTRL + ALT + DEL и/или перезагрузки.

Ответ 25

Причины этих проблем:

  • На этом порту, как Skype, может работать любое одно приложение.
  • Node может быть разбит, и порт, возможно, не был освобожден.
  • Возможно, вы попытались запустить сервер более одного. Чтобы решить эту проблему, можно поддерживать логическое значение, чтобы проверить, запущен ли сервер или нет. Его следует запускать только в том случае, если boolean возвращает false или undefined;

Ответ 26

Возможно, вы используете несколько серверов. Вы можете закрыть их и использовать один сервер. В Linux вы можете использовать команду killall node.

Ответ 27

server.close() занимает некоторое время, чтобы закрыть соединение, поэтому мы должны сделать это асинхронным вызовом как таковым:

ВАЖНО: при использовании await мы должны использовать ключевое слово async в нашей функции инкапсуляции как таковой:

Ответ 28

Вы можете столкнуться со сценариями, в которых даже уничтожение потока или процесса не приведет к прекращению работы приложения (это иногда случается со мной в Linux и Windows). Иногда у вас уже может быть запущен экземпляр, который вы не закрыли.

В результате таких обстоятельств я предпочитаю добавить в свой package.json :

Затем я могу позвонить им, используя:

При желании вы можете сделать это и сделать эти команды BIN с флагом аргумента. Вы также можете добавить их в качестве команд для выполнения в предложении try-catch.

Ответ 29

Будьте осторожны, что, как и я, у вас нет другого окна DOS (или подобного), которое вы забыли о x)

Он произвел точную ошибку, показанную выше!

Ответ 30

Это означает, что у вас есть два сервера node, работающих на одном и том же порту, если один из них работает на порту, скажем, 3000, изменив другой на другой порт, скажем 3001, и все будет хорошо работать

Источник

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