Jeremy M wrote:
I've tried everything on this one, but can't figure out what's going
on. I have a router with 4 internal network interfaces with 4 instances
of Dnsmasq 2.51 running independently on each one. All systems on the
network get DHCP responses without problems, except for machines running
Windows Vista. When running from the router, Vista will simply not
accept the DHCP response even though requests are all being logged
correctly. I've tried connecting over wired, wireless (through a WAP)
and different network segments/interfaces, but Vista will not accept a
response from anywhere.
For wireless, I'm running DD-WRT (http://www.dd-wrt.com/site/index) in
wireless access point (WAP) mode, so having exhausted everything else, I
tried enabling Dnsmasq (running version 2.45) on the WAP as a last
resort and for some reason, that works fine with Vista. I tried copying
the config exactly as on the router (with some interface tweaks), but it
won't work. I'm still running DHCP off the WAP just for Vista, but
would prefer to run on the router to centralize services and keep access
logs.
I've gone as far as running a packet sniffer on the router, and it
appears to be sending responses, but for some reason, Vista just won't
accept them.
Any thoughts or suggestions on why Vista won't accept responses from one
running instance of Dnsmasq (running on router), but will from another
(running on WAP)?
Regards,
Jeremy M.
Well, I guess the obvious question is "are there any differences between
the responses from dnsmasq 2.45 and dnsmasq 2.51" Wireshark works really
well at decoding these things, but if you're not confident at
interpreting what it tells you, feel free to send me packet captures
off-list.
One thing to consider is that vista (unlike almost all other DHCP
clients) demands that the DHCP server sends back all responses as
broadcasts. Inappropriate firewall rules on the system running dnsmasq
2.51 which block these broadcasts would give exactly the symptoms you
are seeing.
Simon.
