Cloudflare sends my IPv6 to the application

Website, Application, Performance DNS & Network
1

I have an application in Heroku which has generated some CNAME and I have added them in Cloudflare but I have an error which Cloudflare only sends IPv6 and my app in heroku requires an IPv4.

To be more specific, I have a subdomain admin.example.com that uses a firewall to block IP addresses that have not been whitelisted. My IPv4 is whitelisted, but I am unable to access the application because Cloudflare sends my IPv6 to the application when I attempt to do so. And I can’t whitelist my IPv6 because it’s dynamic.

2

Hi!

Check if the pseudo IPv4 feature can solve your issue:

https://support.cloudflare.com/hc/en-us/articles/229666767-Understanding-and-configuring-Cloudflare-s-IPv6-support#h_877db671-916a-4085-9676-8eb27eaa2a91

Take Care!

3

No, this does not work for me

4

There are multiple ways to resolve this.

  1. My preference would be to use a Cloudflare Access policy on this admin hostname, and stop allowlisting IP addresses entirely.

  2. Fix your application to allow the use of IPv6 addresses.

  3. Disabke IPv6 on your client device. (See your operating system documentation for instructions)

  4. Disable IPv6 on your zone using the API.

5

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