Enable IPv6 on Docker Bridge Networks: Step‑by‑Step Guide

Docker does not enable IPv6 by default, but many workloads require it. This article explains how to enable IPv6 support on Docker bridge networks, assuming you have a public IPv6 address block.

First, obtain your IPv6 address from the host provider or by running ip -f inet6 addr show eth0. The global‑scoped address (e.g., 2607:f0d0:1002:51::4/64) is the one to use.

1. IPv6 Subnet Division

Similar to IPv4 private subnets, you can divide your IPv6 block into multiple subnets. Use an IPv6 Subnetting Calculator to split, for example, into four /66 subnets:

2607:f0d0:1002:51::/66
2607:f0d0:1002:51:4000::/66
2607:f0d0:1002:51:8000::/66
2607:f0d0:1002:51:c000::/66

2. Configure Docker Daemon for IPv6

Edit (or create) /etc/docker/daemon.json and add the following entries, adjusting the subnet to match your first /66 block:

{
  "experimental": true,
  "ipv6": true,
  "ip6tables": true,
  "fixed-cidr-v6": "2607:f0d0:1002:51::/66"
}

If you prefer to manage firewall rules yourself, set "ip6tables": false or remove the key. After saving, restart Docker: systemctl restart docker Docker now has IPv6 support.

3. Optional: Enable IPv6 in Docker Compose

When using Docker Compose, define the network with IPv6 enabled and a different subnet than the daemon configuration:

networks:
  example:
    enable_ipv6: true
    driver: bridge
    driver_opts:
      com.docker.network.enable_ipv6: "true"
    ipam:
      config:
        - subnet: 172.23.0.0/16
        - subnet: "2607:f0d0:1002:51:4000::/66"
          gateway: 2607:f0d0:1002:51:4000::1

Adjust the IPv6 subnet and gateway to suit your environment.

Reference

https://docs.docker.com/config/daemon/ipv6/