openresolv-discuss

Hi Daniel

On 29/08/2019 12:44, Daniel Letkiewicz wrote:
> Hi guys,
>
> I'm sorry if this is the well-known issue but it seems that resolvconf 
> doesn't clear dnsmasq cache via DBus when the configuration is changed.
> I use OpenVPN + resolvconf + dnsmasq (with DBus) to manage DNS server / 
> domain via VPN tunnel. Everything works fine for me but I had to modify
> https://github.com/rsmarples/openresolv/blob/master/dnsmasq.in#L206 to 
> clear dnsmasq cache.
> I've just added the following command before line 206.
>          dbus-send --system --dest=uk.org.thekelleys.dnsmasq \
>                  /uk/org/thekelleys/dnsmasq uk.org.thekelleys.ClearCache
>
> Otherwise, when my VPN tunnel is down all record received from DNS 
> server exposed via the tunnel stay in dnsmasq cache what is incorrect.
>
> Is there any better way to do that ?

I would argue that it's a regression in DNSMasq.
See line 196: # Send even if empty so old servers are cleared
This imples that old servers are cleared, and thus any cache would be as 
well. Maybe ask upstream if this is a designed change or a regression.

If it's a designed change, then the clear cache needs to happen after 
setting servers, not before.

Roy