[Dnsmasq-discuss] why does dnsmasq reject lease request?

[Simon Kelley]

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Some possible confusion here between DNS servers and DHCP servers. If
the two _DNS_ servers the OP refers to are both also DHCP servers,
then Jim's advice is good. If the OP has two DNS servers, one of which
is dnsmasq which is also acting as the DHCP server (which is how I
read it) then the problem looks like a broken DHCP client, which is
attempting to restart using a DHCP lease it has on some other DHCP
server.

On receipt of the DHCPNAK reply, it should react by doing a
DHCPDISCOVER and find a DHCP server and lease from scratch, rather
then continually retrying. A work around may be to remove whatever
state the broken DHCP client has (/var/lib/dhcp or similar, forget
leases using the GUI in Windows/Apple, factory reset for IoT-type stuff.

Cheers,

Simon.


On 02/02/17 14:00, Jim Alles wrote:
> Hello Will,
> 
> You would need a wireshark capture to see the issue here, the log
> does not tell the whole story.
> 
> It would appear that both DHCP servers are answering the clients's
> requests.
> 
> We don't know your network configuration, or how the ISP's 'router'
> is set up to be able to say for sure. But you should limit the IP
> range of each to avoid the other.
> 
> What I do, is use dnsmasq in a (mostly) open source GUI wrapper
> called NGFW by Untangle. It can replace the
> NAT/router/firewall/DNS/DHCP services of the ISP device, if you get
> it (ISP device) into bridged mode. You would have to provide for a
> Wi-Fi Access Point separately.
> 
> What is your ISP?
> 
> Nice .conf, for home, BTW.
> 
> Jim A.
> 
> On Wed, Feb 1, 2017 at 5:39 PM, Will Parsons
> <varro at nodomain.invalid <mailto:varro at nodomain.invalid>> wrote:
> 
> I have two DNS servers on a single network - one on the router 
> provided by the ISP and one running dnsmasq on one of my own
> machines (which I'd like to be preferred if it's available).
> 
> 
> 
> _______________________________________________ Dnsmasq-discuss
> mailing list Dnsmasq-discuss at lists.thekelleys.org.uk 
> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
> 
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