What causes the getaddrinfo EAI_AGAIN error in Node.js?

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1

I’m seeing a getaddrinfo EAI_AGAIN error in my Node.js app when trying to connect to a Shopify domain.

It seems to be a DNS resolution issue.

I’d like to understand what triggers the EAI_AGAIN error, whether it’s temporary, and how it relates to the dns.js module in Node.

Any insight on handling or simulating eai_again errors?

2

I ran into the getaddrinfo EAI_AGAIN error when deploying a Node.js script that made frequent API calls to a third-party service.

It turned out to be a temporary DNS lookup failure basically, Node.js couldn’t resolve the domain name at that moment.

For me, it was caused by flaky internet.

A quick fix was restarting my router, but in production, I added a retry mechanism with some delay between attempts, which helped a lot.

Also, make sure your DNS server (especially in cloud VMs) is stable, sometimes switching to Google DNS (8.8.8.8) worked wonders.

3

In my case, this error only appeared inside Docker containers.

Outside of Docker, everything resolved fine.

After digging, I found it was due to Docker’s internal DNS resolver having issues when the host system had VPNs or custom DNS settings.

To solve it, I explicitly set DNS in my docker-compose.yml like this:

yaml
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dns:
  - 8.8.8.8
  - 8.8.4.4

That made the eai_again error go away.

If you’re using containers or proxies, it’s worth checking how DNS is being resolved internally.

4

@nehagupta.1798 Yep, I’ve seen EAI_AGAIN when DNS temporarily fails, usually when the network is overloaded or the DNS provider is slow to respond.

To simulate it, I once pointed my request to a non-existent subdomain or temporarily disconnected the network.

In Node.js, I now always handle it like this:

js
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const https = require('https');

https.get('https://my-store.myshopify.com', (res) => {
  // handle response
}).on('error', (err) => {
  if (err.code === 'EAI_AGAIN') {
    console.error('Temporary DNS issue, consider retrying...');
  } else {
    console.error(err);
  }
});

Graceful error handling is key, especially if your app needs to be resilient to transient network hiccups.