[Dnsmasq-discuss] No DHCP leases handed on bridge interface

[Sébastien Delafond]

On 2016-07-15, Albert ARIBAUD <albert.aribaud at free.fr> wrote:
> No mention of the interfaces it binds to and how? No functional
> equivalent to the interface-related options of dnsmasq?

You can pass interfaces to bind to on the command-line, but it wasn't
necessary in my case.

> Which seems to imply that dnsmasq makes the difference based on the
> interface it receives the request on -- hence my asking how ISC dhcp
> chooses the interfaces it listens to... and how dnsmasq does it.
>
> You might want to check whether the bridge is brought up before or
> after dnsmasq is started.

It's up before I start dnsmasq.

> Also, try combinations of interface= and bind-interfaces.

I've tried with "interface=br.eth0-2 bind-interfaces" but the behavior
stays the same.

> Also, checkout bridge-interface= if it is available in your version of
> dnsmasq.

>From the man page, I had assumed bridge-interface would play a role only
if the bridge interface wasn't assigned an IP.

With "interface=eth0.2 bind-interfaces bridge-interface=eth0.2,br.eth0-2",
dnsmasq refuses to stop with "unknown interface eth0.2", which seems to
be a generic message saying that the interface doesn't have an IP.

With "interface=br.eth0-2 bind-interfaces bridge-interface=eth0.2,br.eth0-2",
dnsmasq clearly states "dnsmasq-dhcp: DHCP, sockets bound exclusively to
interface br.eth0-2 " when starting, and I don't get DHCP leases either.

With "interface=* bind-interfaces bridge-interface=eth0.2,br.eth0-2", no
obvious changes.

Not passing bind-interfaces doesn't seem to affect the result of those
tests.

Cheers,

--Seb