changing to


What process changes /tmp/ ?

It is setting the file to:

# Interface wwan

DNS resolution on the local router fails when it gets set to this. Clients all work fine. I change the file to:


… and resolution works properly again from the router. But something changes it back every so often. I haven’t been able to pinpoint what it is yet…

I’m running 3.10 on the AR300m


Well come to find it is set by udhcpc to go to the upstream dns server. When VPN is active this is blocked by the firewall… so DNS resolution doesn’t work. opkg update fails, etc…

I thought this was set to before? Or maybe I just screwed something up somewhere?

Can anyone else verify?


can you set up custom dns and try?


Yes, I have it set to . All clients connected to the router use this. But on command prompt of the router it uses as set by the upstream DNS in /etc/resolv.conf

If I go into Luci I can set the WWAN interface DNS to be and it will update /etc/resolv.conf. But I’m not sure if this will break the captive portal I’m behind now.


This is actually a problem.

Wether the router should use vpn (as well as its DNS) to communicate or not? Some people want the router will use vpn as well. This will break ddns

Some people only want the client use vpn.


The VPN leak protection stops the router from using the upstream DNS - package installs, firmware upgrades and checks also break.

I would think that if no DNS is manually configured the upstream DNS should be allowed to pass the leak protection. But this is a bad configuration. A warning should be displayed to manually configure one or maybe provide the option to use predefined Cloudflare, OpenDNS, or Google settings. And these IP’s should be allowed through the leak protection.