Browsers stop resolving -> tracert fixes the issue

[scottdarkmass]

I have a few laptops all experiencing the same issue. Not at the same time.

Open browser and never resolves to any site.
Wireshark does not show htttp(s) requests even being made.
All browsers affected at the same time.
Temp fix run tracert to any site and browser starts working properly.

Win 7 and Win10 machines
When the issue occurs there are not network connectivity issues. Access to Exchange via Outlook and connection to shares on file servers are working fine.

Not behind a proxy. Machines that have the problem running same software profile (browsers, av...) do not have the issue when others do. IP/DNS assigned via DHCP server.

No idea what tracert does the fixes things. T

Not a power or port issue since network connectivity is not affected.
Not another application interfering since tracert gets it working.

Any ideas or toubleshooting tips would be really appreciated.

 

[marko55]

May be an ARP issue. When the issue occurs on a computer, try just pinging the default gateway and see if the first ping times out, or takes a long time, or doesn't work at all. If all your internal connectivity is still fine I'm assuming all those devices are on the same local switched network. That's all layer 2 traffic. If a computer's ARP entry for its gateway (your internet router presumably) is aging out (normal) then it tries to talk outside its local network it needs to ARP back out for its gateway. If its not getting a response then it can't talk to its gateway, hence can't get to the internet, however internal traffic will still continue to switch fine. This could explain why you're never even seeing the HTTPS SYN since it won't be sent until the machine knows where to send it after it ARPs out for its gateway.

When you run a trace-route it forces a TTL to be sent back from each hop; first hop being the gateway router. This may be enough to resolve the ARP entry and then the computer will start to be able to talk to it again.

Really taking a shot here...but if this is the case the issue could be with your router. If you're lucky its just a bad cable or something crazy like that.