I'm trying to configure an IPv6 DHCP server in gentoo.

So far:

/etc/dhcp/dhcpd6.conf - subnet snippet:

subnet6 2001:db8:21e:101::/64 {

range6 2001:db8:21e:101::6 2001:db8:21e:101::100;


Cleared out /var/lib/dhcp/dhcpd6.leases, and then ran

touch /var/lib/dhcp/dhcpd6.leases

to ensure it existed.

I've restarted the dhcpd service - using

dhcpd -6 -cf /etc/dhcp/dhcpd6.conf

Now I have a neighbour device set up as a dhcp-relay agent. It's relaying a request, and I can confirm with Wireshark that it reaches the server just fine.

However, I'm not getting a response.

In /var/log/messages:

Feb 27 14:17:30 tb19 dhcpd: Relay-forward message from 2001:db8:21e:101::5 port 547, link address 2001:db8:21e:104:1000:1d32:0:1, peer address fe80::200:cdff:fe11:b24c

Feb 27 14:17:30 tb19 dhcpd: No subnet found for link-address 2001:db8:21e:104:1000:1d32:0:1.

I've no idea where the 104 is coming from - it's not mentioned in the dhcp6d.conf or on the devices, and certainly not in the captured packet.

Any theories or suggestions?



Final solution - the 104 is the other interface on the relay-agent.

So since this is the actual subnet I want the v6 address for, I added this subnet to the dhcpserver dhcpd6.conf file:

subnet6 2001:db8:21e:104::/64 {

range6 2001:db8:21e:104::10 2001:db8:21e:104::100;


Lo and behold, next time the DHCP6 solicit is sent out, I get an advertise message back from the server, a request, and a reply, and we've got IPv6 DHCP working :)

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