Remove GUA Addresses for internal Systems from DNS

Installing and Using OpenWrt
1

Hello,

I am lookig for a solution to only have the ULA Adresses (instead of GUA and ULA) in DNS for my internal systems.
Background: I have changed my ISP and now my IPv6 Prefix changes quite often (at least once per day and for every ifdown/ifup on the WAN6 Interface). To make the interal connections stable (via ipv6) I would prefer to simply use the ULA addresses for all internal ipv6 traffic. My Idea was that this could be achieved by not haveing the GUA Address in DNS so that the ULA Adress would be automatically chosen for communications. But after some investigations, I am stuck on how to achive.

Any hints?

Cheers,
Michael

P.S. this is all on an openwrt 23.05.5 based router

2

One option is to use masquerade6 for WAN and not assign GUAs to the internal network.

1 Like
3

What is your reason for this?

My recommendation is:
Please use ULA and GUA addressing in parallel.
Put static or DHCPv6 static assignments with ULAs in your internal DNS.
Avoid NAT66 or NAT-PT.

4

I assume you asked me?

Because the OP specifically asked:

Additionally, some devices only use SLAAC.