Re: force IPv6 SLAAC

Yes - you make a good point about the rules for the DUID. So I'm back to using different NM profiles or a script that sets a different static IPv6 address depending on the VLAN RA,


On Thu, 13 Feb 2020 at 12:26, Bjørn Mork via networkmanager-list <networkmanager-list gnome org> wrote:
Anthony Fletcher <arif bifb org> writes:

>> > My situation is with laptops in a large organisation with a central
>> > DHCP service. The DUID is static and so the laptop gets the same IPv6
>> > address even when it's moved to a different VLAN with a different
>> > prefix. When  I realise the IPv6 address is not appropriate I delete
>> > the lease file and then it all works until the laptop moves VLANs
>> > again.

This sounds like a severely misconfigured DHCP server.  If it serves
multiple network segments then it has to keep separate lease databases
for each network.

>> It sounds like you are in fact connecting to different networks
>> (VLANs). I guess, usually you would have different connection profiles
>> for each network.

The client shouldn't need to know anything about the network. Isn't that
the point of both DHCP and SLAAC?  Else it wouldn't be autoconfiguration...

> Could generating a fresh random DUID each time be a future option for a
> profile?

Yuck.  What point would the DUID serve then?

RFC3315 says

 "the DUID used by a client or server SHOULD NOT change over time if at
  all possible"


DUIDs should never change.  Expect all sorts of trouble if it ever does,
in all properly configured networks that is.

It sounds like you are dealing with a non-functional network. This
cannot be fixed at the client side. The best way to work around the
issues, if you only manage the client, is to configure static

networkmanager-list mailing list
networkmanager-list gnome org

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]