GL-AX1800/4.2.1: repeatedly setting wrong ipv6 unique local prefix

Technical Support for Routers
1

Hi,
I’m having a GL-AX1800, running under 4.2.1, which I want to connect to a company network using wireguard and still having issues.

One problem I have observed:

I have set an IPv6 ULA Prefix in Luci->Network->interfaces->global network options and set a subprefix in the Luci->Network->interfaces->Interface->Advanced Settings. This works for some time.

Since I am currently having issues and problems to connect the AX1800 with a router of different brand, I am changing the Wireguard settings in the GL.iNet Admin Panel repeatedly.

But when I changed the wireguard settings (pureley IPv4 at the moment), I observerd several times that the Router reset it’s IPv6 ULA Prefix (although IPv6 is not part of the wireguard configuration) to dde2:cad1:9115::/48

There’s two severe problems with that:

  1. It breaks all network settings and permissions and such a lot of functionality if the router “automatically” changes the ULA Prefix without Admin’s interaction.

  2. This ULA Prefix is simply wrong, not valid. Afaik this is not an assigned IPv6 range at all. IPv6 ULA addresses must be in the range fc00::/7 , which dde2:: obviously isn’t. This breaks functionality even more, since several services have access restrictions whitelisting fc00::/7 by default, which do not allow dde2:…

So two question:

Why is the router magically changing the ULA setting?

Why does it enforce an invalid IPv6 address?

regards

1 Like
2

Still no comment?

Anyone else observing the same problem?

3

Please try the following command:

echo -e "boot() {\ntrue\n}" >> /etc/init.d/gl_ipv6
sync

And please let me know if the problem has been fixed.

Best regards

4

I just tried it. Seems to work, after having to set the IPv6 ULA prefix in the OpenWRT UI again.

But that is no proof that the problem has been fixed, because it always worked for some time after applying the IPv6 ULA prefix to the OpenWRT UI, until any changes were made in the GL UI, which then overwrote the OpenWRT settings. I have to work with it for some time to see, whether my changes are stable now and not overwritten by GL anymore.

5

It does not work with firmware 4.4.6 anymore.

The router now permanently enforces these wrong dde2 addresses.

But how is this possible? Can’t Gl-Inet fix such an obivous bug? Where did this come from? Someone without knowledge of IPv6 structure writing the software?

6

This is appenently supposed to be a feature…

I have commented that i would like to see an option to turn this functionality off, but currently they are deliberately replacing the “fdxx” with “ddxx” in an init.d script (i think they were using sed) based on a couple of different environment variables (current ipv6 settings, pregenerated prefix, state of some config files)

@hadmut Maybe support my request to make this optional. It has come up multiple times over the last couple of years and should really be fixed