Hosting a NodeJS app - all addresses are in use

Hi, im trying to host a simple NodeJS app.

When running it. All ports I try are in use.

This is my Dockerfile:

FROM node:18.9.0


ADD . /app

COPY . .

RUN npm install

RUN npm run build


CMD [ "node", "./index.mjs" ]

Fly IO config is default with also the app on port 8080.

No matter what port I try:

Error: listen EADDRINUSE: address already in use

Also tried and ports 3000, 3030 and 1337.

Hi Elmar, could you please post the fly.toml configuration and the index.mjs code fragment responsible for starting the HTTP listener? You application should be accessible at <application-name>, it not clear why you try to access it at and

This is an error from the build logs when doing the health check. Im not trying to access the app from there. Its simply not deploying. When Fly tries to run the node app it says address is in use.


# fly.toml file generated for zifera-marketing-site on 2023-02-15T14:17:28+01:00

app = "marketing-site"
kill_signal = "SIGINT"
kill_timeout = 5
processes = []

  PORT = 8080

  auto_rollback = true

  http_checks = []
  internal_port = 8080
  processes = ["app"]
  protocol = "tcp"
  script_checks = []
    hard_limit = 25
    soft_limit = 20
    type = "connections"

    force_https = true
    handlers = ["http"]
    port = 80

    handlers = ["tls", "http"]
    port = 443

    grace_period = "1s"
    interval = "15s"
    restart_limit = 0
    timeout = "2s"


import express from 'express';
import { handler as ssrHandler } from './dist/server/entry.mjs';

const app = express();

app.listen(process.env.PORT || 8080);

The configuration and code look correct. Haven’t you tried to destroy the application using 'fly destroy <application_name> and start deployment again?

Same problem

 1 desired, 1 placed, 0 healthy, 1 unhealthy [restarts: 2]
Failed Instances

Failure #1

99fbcd86        app     0       ams     run     failed                  2               16s ago

Recent Events
TIMESTAMP               TYPE            MESSAGE                                                         
2023-02-16T11:57:21Z    Received        Task received by client                                        
2023-02-16T11:57:21Z    Task Setup      Building Task Directory                                        
2023-02-16T11:57:23Z    Started         Task started by client                                         
2023-02-16T11:57:25Z    Terminated      Exit Code: 1                                                   
2023-02-16T11:57:25Z    Restarting      Task restarting in 1.201671134s                                
2023-02-16T11:57:31Z    Started         Task started by client                                         
2023-02-16T11:57:33Z    Terminated      Exit Code: 1                                                   
2023-02-16T11:57:33Z    Restarting      Task restarting in 1.121943241s                                
2023-02-16T11:57:38Z    Started         Task started by client                                         
2023-02-16T11:57:40Z    Terminated      Exit Code: 1                                                   
2023-02-16T11:57:40Z    Not Restarting  Exceeded allowed attempts 2 in interval 5m0s and mode is "fail"
2023-02-16T11:57:40Z    Alloc Unhealthy Unhealthy because of failed task                               
2023-02-16T11:57:40Z    Killing         Sent interrupt. Waiting 5s before force killing                

2023-02-16T11:57:31Z   [info]}
2023-02-16T11:57:31Z   [info]Node.js v18.9.0
2023-02-16T11:57:32Z   [info]Starting clean up.
2023-02-16T11:57:37Z   [info]Starting instance
2023-02-16T11:57:37Z   [info]Configuring virtual machine
2023-02-16T11:57:37Z   [info]Pulling container image
2023-02-16T11:57:37Z   [info]Unpacking image
2023-02-16T11:57:37Z   [info]Preparing kernel init
2023-02-16T11:57:38Z   [info]Configuring firecracker
2023-02-16T11:57:38Z   [info]Starting virtual machine
2023-02-16T11:57:38Z   [info]Starting init (commit: 617e840)...
2023-02-16T11:57:38Z   [info]Preparing to run: ` node ./index.mjs` as root
2023-02-16T11:57:38Z   [info]2023/02/16 11:57:38 listening on [fdaa:0:bfa5:a7b:23c2:99fb:cd86:2]:22 (DNS: [fdaa::3]:53)
2023-02-16T11:57:39Z   [info]Server listening on
2023-02-16T11:57:39Z   [info]node:internal/errors:484
2023-02-16T11:57:39Z   [info]    ErrorCaptureStackTrace(err);
2023-02-16T11:57:39Z   [info]    ^
2023-02-16T11:57:39Z   [info]Error: listen EADDRINUSE: address already in use
2023-02-16T11:57:39Z   [info]    at Server.setupListenHandle [as _listen2] (node:net:1485:16)
2023-02-16T11:57:39Z   [info]    at listenInCluster (node:net:1533:12)
2023-02-16T11:57:39Z   [info]    at doListen (node:net:1682:7)
2023-02-16T11:57:39Z   [info]    at process.processTicksAndRejections (node:internal/process/task_queues:83:21) {
2023-02-16T11:57:39Z   [info]  code: 'EADDRINUSE',
2023-02-16T11:57:39Z   [info]  errno: -98,
2023-02-16T11:57:39Z   [info]  syscall: 'listen',
2023-02-16T11:57:39Z   [info]  address: '',
2023-02-16T11:57:39Z   [info]  port: 8080
2023-02-16T11:57:39Z   [info]}
2023-02-16T11:57:39Z   [info]Node.js v18.9.0
2023-02-16T11:57:39Z   [info]Starting clean up.
--> v0 failed - Failed due to unhealthy allocations - no stable job version to auto revert to and deploying as v1 

Thanks for the log, probably there is something with setupListenHandle:

Could you try to run something simple as:

import express from 'express';
const app = express();
app.get('/', (req, res) => {