Getting "Error 521: Web server is down" emails - but the IP isn't mine

I’ve recently starting getting this “Error 521: Web server is down” in several emails, but each time the site is absolutely fine and when I check the IP, it’s not the IP of my server.

Now, one quick note is - I’ve recently installed Ezoic (ad platform) on my site and I’m using their Cloudflare integration:

But, I reached out to them and the IPs aren’t theirs either.
So, I’m sort of confused :slight_smile:
Any help is appreciated.

If the IP address starts with a 104, that’s most likely Cloudflare’s public IP address for your server. This is normal for sites using Cloudflare.

Hi @hanriseldon, were the emails from Cloudflare indicating your origin server was unreachable? If so, here is some background, Community Tip - Email alert, origin unreachable.

As @sdayman, mentioned, if it references a 104 ip, that’s cloudfare, but that is not your origin ip.

It concerns me that the email is not actionable. Can you share the name of the domain this was regarding?

Thanks for the answers here.
First, no - the IPs don’t start with 104 - here’s an example:

Server Unreachable for []

Requests to the following origin have been failing for at least five minutes: : []


Thank you, really appreciate the detail @hanriseldon.

I’m in discussion with the team and they’re investigating to see why you received the incorrect information. Really sorry for the confusion.

Hi @hanriseldon, are you using any amazon EC2 services(load-balancer, auto-scaling, etc.) that may dynamically allocate IPs and instances?