DNS resolving issues

[Thebrynn 1]

Let me first state that in general I am quite happy with the service of AirVPN. it has proven to be fairly stable and quite fast!

 

that said, on to the topic at hand.

 

background

I use an Asus RT-AC88U with DD-WRT and an openvpn profile. Last week I had to swap servers because the speed was very much throttled. This worked out fine and now I am back to full speed.

I use the following DNS:

10.4.0.1

10.6.0.1

82.211.31.248 (open nic one)

 

I make sure that Recursive DNS Resolving is on

 

problem statement

Ironically certain websites don't work. Ironically because airvpn.org is one of them.Setting up an extra tunnel from my pc resolves it most of the time. But DNS wise etc these are the same settings.

 

troubleshooting:

doing an nslookup on the third dns with airvpn works fine.

nslookup airvpn.org 82.211.31.248 on my win 10 machine resolves this properly.

Using nslookup airvpn.org 10.4.0.1 on my Win10 machine I get DNS timeouts.

 

it's like only the first DNS is being used. also when I just use nslookup I get the same timeouts like on the first DNS server.

 

creating an extra tunnel on the pc allows me to resolve most unresolved entries.

 

Does anyone have any ideas on what the cause could be? It's just an annoyance that I have to create an extra tunnel for specific websites.

 

Thanks in advance

[Thebrynn 1]

some more troubleshooting.

 

I figured, well if it works with an opennic dns, let's put that one in as a primary ... well that did not work either.

It's like openvpn is not using the dns's I put in there.

 

only when I an extra tunnel it seems to work on my win10 box

 

So something on my router is not working as it should, as when I ssh into the router, I can't seem to resolve the airvpn.org entry.

[zhang888 1066]

If you run the OpenVPN client on the router, you should set the 10.4.0.1 DNS on your router, and use the IP of your router

in your devices DNS server address, this is a more correct approach.

 

Depending on your network setup, if your VPN client runs on the router, there is a good chance LAN machines will not be

able to access 10.4.0.1 - there is no 10.4.0.1 gateway for them to forward it to, unless you make a special static route.

[Thebrynn 1]

hey all, I fixed this issue after a quite a bit of troubleshooting.

 

The short version.

 

It was purely router related issue. I noticed I started to have some mtu fragment problems. As soon as I fixed that (reset MTU back to 1500 aply mssfix again) for a few seconds I could access airvpn.org.

 

The next thing I tackled was the DNS configuration of the router again, I reset them back to default, then started applying the settings and testing piece by piece.

What worked for me was enabling and then disabling recursive DNS lookups.

 

happy that it works now, Thanks Zhang888 for your thoughts / input. My computers get my router as the DNS/Gateway indeed. Default setting from my DHCP.

[T2%57_ct5 2]

Hello,

 

This may be my issue, but, how did you do this:

 

 It was purely router related issue. I noticed I started to have some mtu fragment problems. As soon as I fixed that (reset MTU back to 1500 aply mssfix again) for a few seconds I could access airvpn.org.

 

The next thing I tackled was the DNS configuration of the router again, I reset them back to default, then started applying the settings and testing piece by piece.

What worked for me was enabling and then disabling recursive DNS lookups.

 

what did you do to fix the mtg fragment problems? on your router? what is misfit....I have the 10.4.0.1 set as the DNS server on my mac, and after a few disconnects (over a couple of days), the Eddie gets stuck checking routes. I think it looses the DNS server to resolve.

 

thanks