[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 :)

  • @IHawkMike
    link
    711 months ago

    Check the following during this unknown network window:

    • What does ipconfig /all show
    • Can you ping the gateway?
    • What does arp -a show?
    • Is there anything in the NCSI log?

    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?

    • DyskolosOP
      link
      fedilink
      411 months ago

      NVM, I finally found the culprit by accident…my switch enabled STP (slow) by default. Switching it off or using RSTP fixed the delays. Thanks for helping anyway man!

    • DyskolosOP
      link
      fedilink
      211 months ago

      Will do the bootup-script! Good idea.

      The wireless were on a different VLAN. Also changed that for troubleshooting. Now everything is the same and got the same firewall-rules. Which i also completely disabled. And no, DHCP is the same for all too.