[Dnsmasq-discuss] dnsmasq on an IPv4 /32 interface

[Paul Gear]

On 22/9/20 4:22 pm, Nicolas Cavallari wrote:
> On 21/09/2020 21:32, Paul Gear wrote:
>> Hi all,
>>
>> I've been trying to solve the same problem described in this blog post:
>> https://blog.fhrnet.eu/2020/03/07/dhcp-server-on-a-32-subnet/
>>
>> In a nutshell, the situation is a VM host which performs routing and
>> firewalling for all its guests, providing an isolated IPv4 /32 (and in
>> my case an IPv6 /64 or /128 as well) to each VM guest, and using
>> interface routes on the host to direct traffic to each guest, without
>> wasting IPv4 addresses on /31 or /30 point-to-point links.
>> ...
> This sounds like the use case for shared-network:
>
> shared-network=virbr13,192.168.1.26
>
> or
>
> shared-network=172.16.0.1,192.168.1.26
>
> Alternatively, i sent this patch a while ago to be able to ignore any
> matching, but my use case is different. I can send an updated version if
> people are interested.
>
> http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2018q1/012070.html


Ah, perfect - thanks very much, Nicolas.

I was doing my testing using the OS-packaged dnsmasq on my laptop, which
was 2.79.  Looks like shared-network was added in 2.81.  I'll upgrade
and do some testing, but it looks from the description like this is
exactly what I'm looking for.

Much appreciated.

Regards,
Paul