DHCPv6 client in Windows 10 broken after anniversary update

[Mikael Abrahamsson]

On Mon, 10 Oct 2016, Harald F. Karlsen wrote:

> Hi,
>
> It seems like Microsoft somehow broke DHCPv6 client functionality in the 
> Windows 10 anniversary update and now neither stateful nor stateless DHCPv6 
> functionality works unless you manually issue "ipconfig /renew6" (for 
> stateful DHCPv6 this will only give you IPv6-connectivity untill the lease 
> expires).

I did some tests here with two different (fully updated) Win10 machines 
(both installed from MS-downloaded image).

I actually can't get it to get either of them to do DHCPv6 IA_NA at all 
now.

Ubuntu machines asked asked and received IA_NA as soon as they saw the RA.

MacOS and iOS devices asked for IA_NA after reconnect (they didn't trigger 
any action from the transiston from M=0 to M=1).

Both Win10 machines doesn't seem to be able to ask configure IA_NA at all. 
I did manage to get the first one to do IA_NA successfully with a 12 hour 
lease, then I mucked around with the lease times (lowered it to 10 
minutes) and deleted the lease database, now it won't do any IA_NA at all.

Now I am running with 1 hour default lease.

It does request it:

13:56:55.331732 IP6 (hlim 1, next-header UDP (17) payload length: 108) 
fe80::c16d:fb79:e041:a45c.546 > ff02::1:2.547: [udp sum ok] dhcp6 confirm 
(xid=3bfb7d (elapsed-time 0) (client-ID hwaddr/time type 1 time 523922923 
305a3ae24695) (IA_NA IAID:120609338 T1:0 T2:0 (IA_ADDR 
XXXXX:1ff:: pltime:0 vltime:0)) (vendor-class) 
(option-request vendor-specific-info DNS-server DNS-search-list))

13:56:55.333490 IP6 (hlim 64, next-header UDP (17) payload length: 82) 
fe80::26a4:3cff:feb3:b2e5.547 > fe80::c16d:fb79:e041:a45c.546: [udp sum 
ok] dhcp6 reply (xid=3bfb7d (client-ID hwaddr/time type 1 time 523922923 
305a3ae24695) (server-ID hwaddr/time type 1 time 529405186 24a43cb3b2e5) 
(status-code success))

It just doesn't configure it afterwards. It COULD be some kind of problem 
in my ER5, because this lease actually doesn't show up in the leases 
database on the ER5 when I use the show command there.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se