Error 523 Origin Is Unreachable | How To Fix?

When Cloudflare encounters error 523, it means that the origin web server has stopped functioning properly and cannot be reached.

As a part of our Server Management Services, Skynats regularly receives requests to resolve Cloudflare errors.

Let's see how our support engineers resolve this issue for our clients today.

Why does this error 523 origin unreachable occur?

Let's examine the cause of this 523 error before moving on to the solution.

The connection between Cloudflare and the original web server is generally the cause of this error. Furthermore, it suggests that although the browser can connect to Cloudflare, Cloudflare is unable to connect with the original server.

The one who acts as a middleman between the user and the website server is Cloudflare.

This can occur for numerous reasons, such as the following:

• Changes in DNS settings

• Issue with internet routing

• Cloudflare Railgun problems

Finally, using the browser to access the website results in:

1. Change in DNS settings

If you encounter an error such as "Error 523 Origin Is Unreachable," this should be the first and most crucial thing to be checked.

For their clients, the hosting companies occasionally update the IP information for the domain. Cloudflare might not be informed of the modification, though. In such circumstances, it is necessary to confirm that the Cloudflare DNS settings reflect the new origin IP address for our A record.

2. Internet routing problems

Similar errors are produced when there are issues with internet routing between Cloudflare's systems and the original web server. This may be the result of firewall restrictions, network issues, and many other things.

3. Issues with Cloudflare Railgun

The Cloudflare Railgun can also result in a 523 error.

Let's take a quick look at Cloudflare Railgun before talking about this issue.

Here, WAN optimization technology called Railgun accelerates the delivery of non-cached pages. It guarantees the fastest possible connection between our origin server and the Cloudflare network.

Railgun users who use Cloudflare Hosting should make adjustments to get the connection to work.

Otherwise, we should change the settings at Cloudflare's end based on how our Railgun server is configured if users are running their own Railgun.

How to fix error 523?

Now let's look at the solution to the error 523 Origin Is Unreachable.

We were recently asked by one of our clients to fix a 523 error on his website.

When we checked, we discovered that the domain's DNS settings were incorrect. To stop DDoS attacks, the original server IP was updated. However, when we searched, we discovered that the client's DNS was still using the previous IP.

As a result, we offered the appropriate DNS configurations and requested that the client add them to the Cloudflare end.