Windows 2012 Nic Teaming pooched

Problem

Something bad happened during a firmware/driver update on one of my servers, which resulted in the network adapters being unavailable for teaming in the native nic teaming module. The server had Broadcom Netextreme II adapters, and we suspect that the BACS application is the culprit, since it also supports teaming. The problem presented the following symptoms:

  • Constant reinstallation of drivers in device manager for several minutes
  • The adapters were missing from Network Connections, but visible in device manager
  • No adapters were available for teaming in Windows Nic Teaming

Solution

  • First you enter device manager and enable Show hidden devices:
    image
  • Look for greyed out devices, that is devices that are not connected. Delete/uninstall all of them. You will probably be left with at least one “Microsoft Network Adapter Multiplexor Driver #n” that you are not able to uninstall.
  • Uninstall ALL broadcom drivers/software and reboot.
  • Open device manager again, and get the guid of the stubborn multiplexor adapters:
    image
  • Go to the HKLM\System\CurrentControlSet\Services\NdislmPlatform\Parameters\Teams registry key:
    image
  • Delete the entire team key that corresponds to the key you found above, that is the key labeled {GUID} under Teams:
    image
  • Reinstall the latest Broadcom drivers without BACS and BASP:
    image
  • Reboot, and re-create the teams using Nic Teaming

Author: DizzyBadger

SQL Server DBA, Cluster expert, Principal Analyst

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