We are encountering an issue with our computers running the L2TP VPN connection outside of the building. We are using the built-in Windows client. It seems that somehow, it's this issue is tied to the Window 10 update KB5015807. We can remove that update on a machine, and the issue resolves itself. For whatever reason, the network drive paths will not authenticate. It seems like it's a DNS issue, but I can't tell for sure. I map them via GP to the hostnames and paths of the server shares.
Here's what I know so far - In relation to these file servers, I can
- Ping their IP Addresses and host names
- Tracert both ip & host (though it takes 3 hops to hit it)
- NSlookup both just fine
Now, if I map the drives manually via IP or Host, it will ask for credentials, with the email@example.com as the username. If I map via IP, it just pops up wanting credentials. If I do it via hostname, it pops up wanting credentials, and underneath that, has an error stating "The system cannot contact a domain controller to service the authentication request. Please try again later.". On a restart, neither way works when you reconnect to the VPN. If you double click on them, you get a "This connection has not been restored" pop-up.
This makes me think that at least initially, it's trying to query for these drives outside of the DNS that we provide on VPN. Our website has the same domain as our internal domain (hoping to change that soon, carry-over from the previous IT guy here). I assume that it's querying the website, though I haven't done a wireshark to prove that yet.
For what it's worth, I've run a netstat -rn and checked metrics, and changed them accordingly so the VPN "Should" be higher priority, though I don't see it in the list. I also added the AssumeUDPEncapsulationContextOnSendRule DWORD to the registry, hoping by dumb luck it was something to do with that. I've also turned DNS Suffixes off and on, added and removed DNS and WINS servers manually, and turned "Use default gateway on remote network" off & on more times than I can count.
For what it's worth, I am very Meraki illiterate, I have only been here about 4 months and had little experience with Meraki before. If there's some secret sauce I'm missing, please call me out on it. Thanks!