[Dnsmasq-discuss] not getting a subnet-mask in dhcp reply, when using multiple instance of dnsmasq

[Brian Davidson]

You appear to have competing settings for subnet.

dhcp-option=lan,1,255.255.255.0
dhcp-option-force=lan,1

Is it intentional?

On Tue, Sep 19, 2023 at 9:28 AM AleksM <a+dnsmasq at alek.cx> wrote:
>
> Hi all,
>
> I'm running on OpenWRT (SNAPSHOT r23935+13-c1206675a4) which has installed dnsmasq 2.89 and my client is a macbook running MacOS 12.3.1 and I recently switched from a single dnsmasq instance to a multi-instance dnsmasq setup (because i wanted a different subdomain name given for the different networks i have dnsmasq listen on and that was the approach suggested in openwrt forum),
>
> But when i performed this change, i found out (after many days of troubleshooting) that the dhcp response no longer contained a subnet-mask field (which was causing my client to use the default /16 for a classful CIDR of that address space, which caused connectivity issues that were hilariously baffling at first).
>
> Is there some bug here, or am I doing something wrong?
>
> Attaching both the single-instance dnsmasq.conf (working) and the DHCPOFFER response as well as the offending instance in the multi-instance dnsmasq.conf (broken) and the DHCPOFFER response, where the subnet-mask option is omitted (despite me attempting to add it as an extra DHCPOPTION #1 even!)
>
> Any advice or anything else to look at?
>
> Warm regards,
> Aleks
> _______________________________________________
> Dnsmasq-discuss mailing list
> Dnsmasq-discuss at lists.thekelleys.org.uk
> https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss