[SOLVED] DHCPv6 and/or Router Advertisements not working

[Rob_H]

Hi all.

I followed this guide to set up IPv6 with my Comcast Xfinity ISP. On the WAN side, I'm using a prefix delegation size of 60. On the LAN side, I've got IPv6 configuration set to Track Interface (WAN) and I turned on RA ("Assisted") and DHCPv6 server. The WAN is getting an IPv6 address and a delegated prefix from the ISP, and the LAN interface is getting an IPv6 address with that prefix. In the diagnostics, ping6 works. All this is great and wonderful!

Now, the problem: None of my clients on the LAN are getting IPv6 addresses (other than link-local). I can see the solicitations go out from one of my Linux hosts, but there is no reply from the router. If I manually configure the host with an IPv6 address in the range, it works fine (19 out of 20 tests pass on https://ipv6-test.com) so it seems to be just the DHCP and/or RA service that's not working. What can I look at to troubleshoot?

Thank you!

[Rob_H]

Solved! I was beginning to suspect it had something to do with the fact that my LAN interface is a bridge. That led me to a Clients don't get an IPv6 address thread and a VLAN on bridge problem thread, which led me to take a closer look at my bridge settings. There, I found a setting labeled Enable link-local address. 💡 Enabled that, rebooted, and like magic, my clients are getting IPv6 addresses now. Yay!

[rabi]

Thanks for sharing.