How to Turn Off IPv6 Support

Last Updated: Feb 20, 2026

Overview

This article explains how to implement a solution for customers whose systems only support IPv4.

For example, a Java-based web server calling Auth0 APIs fails to connect because the Auth0 DNS resolves to an IPv6 address.

Applies To

IPv6 Support
Auth0 APIs

Solution

Auth0, by default, supports both IPv4 and IPv6. Therefore, the canonical Auth0 domain and Auth0-managed custom domain may resolve to IPv4 or IPv6 when a client makes a connection request.

There are two options to force IPv4:

Using a self-managed custom domain, customers with an enterprise subscription can manage the DNS for the login domain to limit IPv6 usage. This solution has the risk of users failing to connect if they are on an IPv6-only network. E.g., the users who are trying to access the universal login page.
A better option may be to configure the server in an IPv4 network to use IPv4 only. This external Q&A may be helpful for Java applications.