On Wednesday 27 January 2016 13:37:27 Pali Rohár wrote: > On Wednesday 20 January 2016 20:15:23 Simon Kelley wrote: > > Dnsmasq identifies IPv6 clients via their MAC address for the > > purpose of selecting dhcp-host configuration to use, but it > > doesn't use the MAC address as a unique client identifier for the > > purpose of assigning DHCP leases in the same way the DHCPv4 does. > > That's the crucial difference. > > Yes, I know. > > > The equivalent of the DHCPv4 share MAC address facility, should > > really be something which shares IAIDs, maybe? > > Right, in lease file is stored pair (MAC address, IP address) for > IPv4 and pair (IAID, IPv6 address) for IPv6. > > > The crucial thing I'm trying to achieve here is turning your patch > > from something that works on your network, with your very odd > > configuration, into something that other people might want and use. > > Without that, it's fine as your patch, but it can't go into the > > dnsmasq mainline. > > Understood. > > > Maybe the way to think about that is to think about > > how to document it. If we can describe what problem it solves, and > > how it should be used, then we'll be getting there. > > I was thinking about it for more days. It is really not easy to solve > this problem... Here are my results: > > * There are people who misuse original concept of "more mac > addresses" for one ipv4 address. Dnsmasq supports this configuration > only if one mac address from that --dhcp-host line is used at same > time. > > * DHCPv6 clients are identified by DUID string, which we can say is > totally random and are not persistent across multi-OS computers or > reinstalling... > > * Internally DHCPv6 leases are identified by IAID. > > So to make configuration clean for both IPv4 and IPv6 we need support > for: > > * Assigning IPv4 lease to more MAC addresses at the same time > (This will help people to use "more mac addresses" functionality > correctly) > > * Assigning IPv6 address to more DUIDs at the same time > (This is "correct" IPv6 equivalent for previous request) > > * Assigning IPv6 address to more MAC addresses at the same time > (This is what would fix DUID problem) > > And it means that pair (IAID, IPv6 address) for IPv6 leases it not > enough to do it. > > So, what about extending lease line for IPv6 addresses to include > DUID and MAC address? > > > We need to bear in > > mind that the behaviour we're talking about violates the RFCs > > specifying DHCPv6, so it has to be especially carefull justified. > > Thats probably truth, but if something is useful users will try to > use it. Either itself by patching dnsmasq or if possible by optional > config options...
Hi Simon! Replaying to my old email from January. Have you found some time to look at my suggestions? If yes, what do you think about it? -- Pali Rohár pali.ro...@gmail.com
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss