Possible clues...?
Notice the output for PROSetCL.exe Adapter_EnumerateSettings 1 (a non-teamed network interface):
1) Intel(R) Ethernet Server Adapter I340-T4 #2
Settings:
LLIPorts -
NetworkAddress -
*ReceiveBuffers - 256
*RssBaseProcNumber - 0
*TransmitBuffers - 512
EnableLLI - Disabled
*FlowControl - Rx & Tx Enabled
*InterruptModeration - Enabled
*IPChecksumOffloadIPv4 - Rx & Tx Enabled
*JumboPacket - Disabled
*LsoV2IPv4 - Enabled
*LsoV2IPv6 - Enabled
*MaxRssProcessors - 8
*NumaNodeId - System Default
*PriorityVLANTag - Priority & VLAN Enabled
*RSS - Enabled
*SpeedDuplex - Auto Negotiation
*TCPChecksumOffloadIPv4 - Rx & Tx Enabled
*TCPChecksumOffloadIPv6 - Rx & Tx Enabled
*UDPChecksumOffloadIPv4 - Rx & Tx Enabled
*UDPChecksumOffloadIPv6 - Rx & Tx Enabled
*VMQ - Disabled
*WakeOnMagicPacket - Enabled
*WakeOnPattern - Enabled
EnablePME - Disabled
ITR - Adaptive
LogLinkStateEvent - Enabled
MasterSlave - Auto Detect
NumRssQueues - 1 Queue
ReduceSpeedOnPowerDown - Enabled
WaitAutoNegComplete - Auto Detect
WakeOnLink - Disabled
Here is the output for PROSetCL.exe Adapter_EnumerateSettings 2 (an interface in the VMLB team):
2) TEAM : VMNetwork - Intel(R) Ethernet Server Adapter I340-T4 #3
Settings:
LLIPorts -
NetworkAddress - 001B21AEB9A5
*ReceiveBuffers - 256
*RssBaseProcNumber - 0
*TransmitBuffers - 512
EnableLLI - Disabled
*FlowControl - Rx & Tx Enabled
*InterruptModeration - Enabled
*IPChecksumOffloadIPv4 - Rx & Tx Enabled
*JumboPacket - Disabled
LSO - Enabled
*LsoV2IPv6 - Enabled
*MaxRssProcessors - 8
*NumaNodeId - System Default
*RSS - Enabled
*SpeedDuplex - Auto Negotiation
*TCPChecksumOffloadIPv4 - Rx & Tx Enabled
*TCPChecksumOffloadIPv6 - Rx & Tx Enabled
*UDPChecksumOffloadIPv4 - Rx & Tx Enabled
*UDPChecksumOffloadIPv6 - Rx & Tx Enabled
*VMQ - Disabled
ITR - Adaptive
LogLinkStateEvent - Enabled
MasterSlave - Auto Detect
NumRssQueues - 1 Queue
WaitAutoNegComplete - Auto Detect
Note the absence of Priority / VLAN settings in the enumerated settings for the teamed interface.
Finally, here is the output for PROSetCL.exe Team_EnumerateSettings 1:
1) TEAM : VMNetwork
Settings:
BalanceInterval - 10
CheckTime - 1000
MaxNumProbeRetry - 10
STForwardDelay - 0
FailbackEnabled - Enabled
ProbeEnabled - Enabled
ProbePacketType - Broadcast Probes
Again, no settings for Priority / VLAN.
As a test, I removed one of the teamed network interfaces from the VMLB team and created a new Hyper-V virtual network (external) connected to the interface removed from the team. On the VM with 2 virtual network adapters, I configured the tagged-VLAN adapter to connect to the newly created virtual network (instead of the virtual network associated with the VMLB team). After booting the VM, I successfully tested basic connectivity on the default (untagged) VLAN and the tagged VLAN.
Are VLANs unsupported on I340-T4 teamed interfaces? I haven't seen anything explicitly stating so, and have seen documentation, threads and posts suggesting the opposite. Well, maybe not for the I340-T4 in particular, but teamed Intel server nics in general.