On Wednesday, September 29, 2021 10:22:27 PM CEST hw wrote: > On Sunday, September 19, 2021 6:53:45 PM CEST Kenneth Porter wrote: > > --On Sunday, September 19, 2021 3:02 PM +0200 hw <hw at gc-24.de> wrote: > > > None of this is working because the server isn't running a DHCPv6 > > > server, > > > and there seems to be no file in /var/lib/NetworkManager that would seem > > > to be helpful. > > > > > > Isn't there a tool that creates the DUID and prints it? This can't be > > > too difficult ... > > > > I found this thread that suggests that NetworkManager computes it every > > time unless it's manually overridden: > > > > <https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/135 > > > > > That might mean that I would need to extract the functions from the soruces > of dhclient to make a program that prints DUID(s) for the machine you run > it on. ... But that isn't so easy. Maybe I can find out how to create a > DUID and write something in perl; it doesn't seem to be too complicated in > the source. > > The comment is interesting: > > /* > * The "best" default DUID, since we cannot predict any information > * about the system (such as whether or not the hardware addresses are > * integrated into the motherboard or similar), is the "LLT", link local > * plus time, DUID. For real stateless "LL" is better. > * > * Once generated, this duid is stored into the state database, and > * retained across restarts. > * > * For the time being, there is probably a different state database for > * every daemon, so this winds up being a per-interface identifier...which > * is not how it is intended. Upcoming rearchitecting the client should > * address this "one daemon model." > */ > > I don't understand what the point of a DUID is which is /not/ a > per-interface identifier. When I assign addresses via DHCP, I don't want > them to end up being assigned anywhere else than to the interface they need > to be assigned to. What is intended with these DUIDs? > Hm, ok, here's an explanation: https://www.juniper.net/documentation/en_US/ junose15.1/topics/concept/dhcp-unique-id-servers-clients-overview.html IIUC, this means that I could create a DUID (of type 1) with an arbitrary time value (Or where would I get the "correct" one?) and enter it into the configuration of a static lease in OPNsense (or any other DHCPv6 server), and it would be totally pointless unless I manage to force the client beforehand to use this DUID to ask for an IP address and unless I can make sure that the client always uses this DUID for a particular interface --- which isn't intended because the DUIDs aren't supposed to identify particular interfaces. Is that my lack of understanding or are these DUIDs really a rather stupid idea? And how are we actually supposed to set up static leases with DHCPv6?