Weird problem driving me crazy (Win, Domain, Network)
Weird problem driving me crazy (Win, Domain, Network)
[Update:Solution]
It was my router which set STP on by default. Switching it off (in smaller networks) or using RSTP made the delays go away.
[/Update]
Hóla!
For a long time I've got this horribly annoying problem: Upon bootup, ANY domain-machine that is using LAN (no probs with wireless) has an idle-time with "there's no network!" of about 1-2mins until they discovered the network. BUT only windows-machines. Linux boxes get net instantly. Also on LAN.
Setup: 2 Domaincontrollers, Server2019. Both are DNS, one is DHCP and NPS for WIFI. All machines have fixed IPs, the DHCP is just for wireless clients.
I have tried everything I could think of, like NIC-Drivers, OpenDHCP, temporarily changed the switch from a managed one to a dumb one, changed the NIC in the server, let only one DC be alive at a time, rejoined the domain, the usual sfc/dism-approach and whatnot.
I asked once on reddit, but everyone just told me "that's DHCP!", yet it's (seemingly at least) not. All have fixed IPs, but using dhcp doesn't change a thing.
So I'm clueless again, hoping for some nerd that's nerdier than me to have an idea :)
Windows machines determine whether they have Internet by pinging a Microsoft server, if there's an issue doing that it would explain why Linux boxes on the same network don't have this problem. As for the root cause, there's nothing in your post that gives me an idea.
Oh, it’s not INTERNET they don’t get, they get no net at all. It’s “unknown network” for a long time until they finally display “” and only then I can access the LAN. From there on, everything works fine.
I know this is stupid to ask but can you test setting up servers fresh from a .iso? No template, no domain join, no nothing that would create any predefined settings. If the issue doesnt persist, maybe there is a legacy gpo or something that forces it for domain recognition before allowing other network traffic. Or something completely different but we gotta corner the problem in with troubleshooting.
And also maybe create a script that's being fired at bootup. The script could write the timecode and the "ipconfig /all" and "route print" into a textfile every few miliseconds.
This would create large logfiles but might help. Since if you are even uncapable of pinging local adresses with IPv4 adresses, maybe the network stack just simply doesn't load fast enough.
Also some additional info might help with cornering it in such as:
Check the following during this unknown network window:
Also are your wireless clients on a different VLAN than your wired clients? Does the firewall treat this traffic differently in any way? Does DHCP give out different DNS settings than wired?
Still sounds like an NCSI issue. You might have active probing disabled or it's not working.