From cdcd86420e83984228dbb027d5f148f3cea9e0c6 Mon Sep 17 00:00:00 2001
From: Brennan Kinney <5098581+polarathene@users.noreply.github.com>
Date: Thu, 14 Mar 2024 15:24:33 +1300
Subject: [PATCH] docs: Add IPv6 troubleshooting tip (#3938)

Sometimes a user may have a configuration error and get halfway there. This should help point them in the right direction.
---
 docs/content/config/advanced/ipv6.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/content/config/advanced/ipv6.md b/docs/content/config/advanced/ipv6.md
index 77dfb0c9..7e9c904c 100644
--- a/docs/content/config/advanced/ipv6.md
+++ b/docs/content/config/advanced/ipv6.md
@@ -177,6 +177,12 @@ docker run --rm -d --network dms-ipv6 -p 80:80 traefik/whoami
 curl --max-time 5 http://[2001:db8::1]:80
 ```
 
+!!! warning "IPv6 gateway IP"
+
+    If instead of the remote IPv6 address, you may notice the gateway IP for the IPv6 subnet your DMS container belongs to.
+
+    This will happen when DMS has an IPv6 IP address assigned, for the same reason as with IPv4, `userland-proxy: true`. It indicates that your `daemon.json` has not been configured correctly or had the updated config applied for `ip6tables :true` + `experimental: true`. Make sure you used `systemctl restart docker` after updating `daemon.json`.
+
 !!! info "IPv6 ULA address priority"
 
     DNS lookups that have records for both IPv4 and IPv6 addresses (_eg: `localhost`_) may prefer IPv4 over IPv6 (ULA) for private addresses, whereas for public addresses IPv6 has priority. This shouldn't be anything to worry about, but can come across as a surprise when testing your IPv6 setup on the same host instead of from a remote client.