NIC Teaming within a Guest VM
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I am trying to understand, in Server 2012r2, what the option "GuestVM>Settings>Network Adapter>Advanced Features> "Enable this network adapter to be part of a team in the guest operating system" does.
In your video it seemed to be stated that this option needed to be set to allow the guest vm traffic to use all the adapters in the Host machine's NIC team. I thought this function was to enable the VM to create multiple virtual network adapters connected to (usually) different virtual switches (each of which is associated with different physical NIC teams going to different physical network switches), thus to provide both redundancy and fault tolerance within the VM.
So for example, say I have 4 1 Gb/s NICs teamed, using LACP. The team is associated with a single hyper-v virtual switch and the VM guests connect to that switch. I would think that the actual teaming of the physical adpaters would be invisible to the VMs and therefore they would physically have access to the combined bandwidth (4 Gb/s) of the teamed NICs (via each of their single 10Gb/s virtual nic). However, the video seemed to imply that unless the above option was ticked, their traffic would only flow through 1 physical NIC (and hence only have 1Gb/s available).
Can you tell me which is correct and in the above example, whether setting the "Enable this network adapter..." would actually make any difference?
Many thanks
Ian
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Ian,
My apologies about the delay in getting to your question!
Both you and the episode are correct in your descriptions. NIC teaming allows for a single VM to have a single Virtual NIC but be able connect to multiple NICs. This means that even if a single physical NIC fails, this wouldn't cause the VM's virtual NIC to fail! So this is cool!
As long as you're not using the SingleRoot IO Virtualization (SR-IOV). SR-IOV connects directly to the virtualization functions on the physical NIC. So this means that if you're using this, your VMs do not take advantage of the NIC teaming provided from your OS network stack at the Management OS. Put differently, SR-IOVs don't see the NIC teaming.
This setting shows that both you and the episode to be right! It allows the VMs to use all of the SR-IOV adapters, This means that the VMs will see 2 Virtual NICs and use them both for the purposes you've stated.
Cordially,
Ronnie Wong
Host, ITProTV
