ANSWERED Tomato router can't resolve after static DNS set up

[lambrusco 1]

I have a Linksys E2500 running Tomato v1.28 (shibby) bought from FlashRouter. It sits behind an old Netgear router which connects to my ISP and is exclusively my VPN router that connects to AirVPN. It has worked without a problem for over 6 months. However on Wednesday, the electricity company cut our power for 6 hours and when the power came back, the router would not connect to AirVPN. Having spent a considerable time trying to debug the problem, I have gone back to first principles and reinitialized the router (doing a thorough erase of NVRAM). After the router came back up, it worked fine as a vanilla router, so I followed the setup instructions at https://airvpn.org/tomato/?hl=tomatohttps://airvpn.org/tomato/?hl=tomato (which is what I did previously). During this process, I noticed a couple of things:

1 After setting my timezone and server, the router did not set its internal clock.

2 The moment I configured any DNS IP into the static DNS slots, the router stopped resolving any domain names. I understand that using 10.4.0.1 will only work when running through a VPN, but I have tried lots of different DNS servers (OpenNIC, my ISP's, Google, etc) and all of them cause name resolution to fail. Once I remove the static entries, resolution returns.

 

I pressed on and completed the VPN setup but could not get the VPN to connect. I tried checking the "Resolved hosts in .ovpn" in the config generator but still no luck. I'm now wondering if my hardware is faulty.

 

Can anyone shed any light on this? I'm new to all this so keeping answers simple would be much appreciated. I guess specific questions that I'd like answered are:

1 Should I see the router clock update correctly after setting timezone and server?

2 Should setting static DNS entries affect name resolution?

3 Does thus sound like a hardware issue?

 

I'm reluctant to flash the firmware as I don't have a copy of what was shipped from FlashRouter (and they don't appear to have it available as a download).

 

Any help would be much appreciated. BTW, I have attached a log file showing all activity from the reinitialize up to the static DNS change and failed ping of google.com.au

syslog2.txt

[lambrusco 1]

In case anyone's interested, I finally got this working. I don't understand the details of why, but I'm just happy that it's working now.

 

The first problem appeared to be with the router clock - it wasn't fetching the date and time from any of the time servers. However, if I manually set an approximate date and time ("date -s 2015.10.31-00:00:00") the router immediately picked up the exact date and time from the time servers. "Approximate" in this context was pretty liberal as I could set it to the beginning of this year and it still picked up the correct time. So I stuck the above command as an Init script and now the router picks up the time every time it starts.

 

The second problem appeared to be my use of UDP to connect to AirVPN. Once I used TCP to connect, it connected reliably (although my speed fell dramatically to roughly one sixth of what I got with UDP). Note that TCP only worked with the clock set and failed to connect otherwise. I have been using UDP (relatively) reliably for six months, so it's a mystery why I can't use it now.

 

Interestingly, I switched from using a UK server (Carinae) to a Canadian server (Gorgonea) and all of a sudden, UDP started working again! However, once I rebooted the router, UDP failed to connect and I was forced back to a slow TCP connection.

 

So here I am, with a working VPN (albeit a slow one) but I am still mystified about what is going on. If anyone can shed any light, I would be very grateful.

[lambrusco 1]

Last minute update: I switched from using port 443 to 2018 and now UDP connects reliably.

 

So I now have reliability and speed!     

[lambrusco 1]

My last response was a furphy - UDP connected once and then refused to connect again.

After a week of crawling along with a TCP connection, I obtained a more recent build of the the Tomato firmware and flashed it.

The result was that the router now obtains its time correctly. resolves domain names with static DNS's configured and connects faultlessly to AirVPN using a UDP/443 connection, giving me the speed that I previously had.

 

Thanks to Tom at FlashRouters for his help in getting this working.