Why does mongo crash inside of docker at random? [duplicate] - node.js

Question

My server threw this today, which is a Node.js error I've never seen before:
Error: getaddrinfo EAI_AGAIN my-store.myshopify.com:443
at Object.exports._errnoException (util.js:870:11)
at errnoException (dns.js:32:15)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:78:26)
I'm wondering if this is related to the DynDns DDOS attack which affected Shopify and many other services today. Here's an article about that.
My main question is what does dns.js do? What part of node is it a part of? How can I recreate this error with a different domain?

Answer 1

If you get this error with Firebase Cloud Functions, this is due to the limitations of the free tier (outbound networking only allowed to Google services).
Upgrade to the Flame or Blaze plans for it to work.

Answer 2

EAI_AGAIN is a DNS lookup timed out error, means it is a network connectivity error or proxy related error.
My main question is what does dns.js do?
The dns.js is there for node to get ip address of the domain(in brief).
Some more info:
http://www.codingdefined.com/2015/06/nodejs-error-errno-eaiagain.html

Answer 3

If you get this error from within a docker container, e.g. when running npm install inside of an alpine container, the cause could be that the network changed since the container was started.
To solve this, just stop and restart the container
docker-compose down
docker-compose up
Source: https://github.com/moby/moby/issues/32106#issuecomment-578725551

Answer 4

As xerq's excellent answer explains, this is a DNS timeout issue.
I wanted to contribute another possible answer for those of you using Windows Subsystem for Linux - there are some cases where something seems to be askew in the client OS after Windows resumes from sleep. Restarting the host OS will fix these issues (it's also likely restarting the WSL service will do the same).

Answer 5

For those who perform thousand or millions of requests per day, and need a solution to this issue:
It's quite normal to get getaddrinfo EAI_AGAIN errors when performing a lot of requests on your server. Node.js itself doesn't perform any DNS caching, it delegates everything DNS related to the OS.
You need to have in mind that every http/https request performs a DNS lookup, this can become quite expensive, to avoid this bottleneck and getaddrinfo errors, you can implement a DNS cache.
http.request (and https) accepts a lookup property which defaults to dns.lookup()
http.get('http://example.com', { lookup: yourLookupImplementation }, response => {
// do something here with response
});
I strongly recommend to use an already tested module, instead of writing a DNS cache yourself, since you'll have to handle TTL correctly, among other things to avoid hard to track bugs.
I personally use cacheable-lookup which is the one that got uses (see dnsCache option).
You can use it on specific requests
const http = require('http');
const CacheableLookup = require('cacheable-lookup');
const cacheable = new CacheableLookup();
http.get('http://example.com', {lookup: cacheable.lookup}, response => {
// Handle the response here
});
or globally
const http = require('http');
const https = require('https');
const CacheableLookup = require('cacheable-lookup');
const cacheable = new CacheableLookup();
cacheable.install(http.globalAgent);
cacheable.install(https.globalAgent);
NOTE: have in mind that if a request is not performed through Node.js http/https module, using .install on the global agent won't have any effect on said request, for example requests made using undici

Answer 6

The OP's error specifies a host (my-store.myshopify.com).
The error I encountered is the same in all respects except that no domain is specified.
My solution may help others who are drawn here by the title "Error: getaddrinfo EAI_AGAIN"
I encountered the error when trying to serve a NodeJs & VueJs app from a different VM from where the code was developed originally.
The file vue.config.js read :
module.exports = {
devServer: {
host: 'tstvm01',
port: 3030,
},
};
When served on the original machine the start up output is :
App running at:
- Local: http://tstvm01:3030/
- Network: http://tstvm01:3030/
Using the same settings on a VM tstvm07 got me a very similar error to the one the OP describes:
INFO Starting development server...
10% building modules 1/1 modules 0 activeevents.js:183
throw er; // Unhandled 'error' event
^
Error: getaddrinfo EAI_AGAIN
at Object._errnoException (util.js:1022:11)
at errnoException (dns.js:55:15)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:92:26)
If it ain't already obvious, changing vue.config.js to read ...
module.exports = {
devServer: {
host: 'tstvm07',
port: 3030,
},
};
... solved the problem.

Answer 7

I started getting this error (different stack trace though) after making a trivial update to my GraphQL API application that is operated inside a docker container. For whatever reason, the container was having difficulty resolving a back-end service being used by the API.
After poking around to see if some change had been made in the docker base image I was building from (node:13-alpine, incidentally), I decided to try the oldest computer science trick of rebooting... I stopped and started the docker container and all went back to normal.
Clearly, this isn't a meaningful solution to the underlying problem - I am merely posting this since it did clear up the issue for me without going too deep down rabbit holes.

Answer 8

I was having this issue on docker-compose. Turns out I forgot to add my custom isolated named network to my service which couldn't be found.
TLDR; Make sure, in your compose file, you have your custom-networks defined on both services that need to talk to each other.
My error looked like this: Error: getaddrinfo EAI_AGAIN minio-service. The error was coming from my server's backend when making a call to the minio-service using the minio-service hostname. This tells me that minio-service's running service, was not reachable by my server's running service. The way I was able to fix this issue is I changed the minio-service in my docker-compose from this:
docker-compose.yml
version: "3.8"
# ...
services:
server:
# ...
networks:
my-network:
# ...
minio-service:
# ... (missing networks: section)
# ...
networks:
my-network:
To include my custom isolated named network, like this:
docker-compose.yml
version: "3.8"
# ...
services:
server:
# ...
networks:
my-network:
# ...
minio-service:
# ...
networks:
my-network:
# ...
# ...
networks:
my-network:
More details on docker-compose networking can be found here.

Answer 9

This is the issue related to hosts file setup.
Add the following line to your hosts file
In Ubuntu: /etc/hosts
127.0.0.1 localhost
In windows: c:\windows\System32\drivers\etc\hosts
127.0.0.1 localhost

Answer 10

In my case the problem was the docker networks ip allocation range, see this post for details

Answer 11

#xerq pointed correctly, here's some more reference
http://www.codingdefined.com/2015/06/nodejs-error-errno-eaiagain.html
i got the same error, i solved it by updating "hosts" file present under this location in windows os
C:\Windows\System32\drivers\etc
Hope it helps!!

Answer 12

In my case, connected to VPN, the error happens when running Ubuntu from inside Windows Terminal but doesn't happen when opening Ubuntu directly from Windows (not from inside the Windows Terminal)

Answer 13

I had a same problem with AWS and Serverless. I tried with eu-central-1 region and it didn't work so I had to change it to us-east-2 for the example.

Answer 14

I was getting this error after I recently added a new network to my docker-compose file.
I initially had these services:
services:
frontend:
depends_on:
- backend
ports:
- 3005:3000
backend:
ports:
- 8005:8000
I decided to add a new network which hosts other services I wanted my frontend service to have access to, so I did this:
networks:
moar:
name: moar-network
attachable: true
services:
frontend:
networks:
- moar
depends_on:
- backend
ports:
- 3005:3000
backend:
ports:
- 8005:8000
Unfortunately, the above made it so that my frontend service was no longer visible on the default network, and only visible in the moar network. This meant that the frontend service could no longer proxy requests to backend, therefore I was getting errors like:
Error occured while trying to proxy to: localhost:3005/graphql/
The solution is to add the default network to the frontend service's network list, like so:
networks:
moar:
name: moar-network
attachable: true
services:
frontend:
networks:
- moar
- default # here
depends_on:
- backend
ports:
- 3005:3000
backend:
ports:
- 8005:8000
Now we're peachy!
One last thing, if you want to see which services are running within a given network, you can use the docker network inspect <network_name> command to do so. This is what helped me discover that the frontend service was not part of the default network anymore.

Answer 15

Enabled Blaze and it still doesn't work?
Most probably you need to set .env from the right path, require('dotenv').config({ path: __dirname + './../.env' }); won't work (or any other path). Simply put the .env file in the functions directory, from which you deploy to Firebase.