I just installed the first Server2025 hyper-v servers.
normally we could use allownetlbfoteam to allow a nic team to be added to a vswitch.
However this is no longer working.

the official solution is to add all interfaces alone to the vswitch. but this is also not working with our LACP switches.

how can we add a LACP team to a vswitch?

2 Spice ups

This is method is deprecated, you need to use SET

Set-VMSwitchTeam (Hyper-V) | Microsoft Learn

SET works with the dumb switches. but i can’t get it to work with LACP.
so the question is… can we get SET working with enterprise hardware? or can we get back to the old teaming?
other option is to re-install the server with 2022.

i prefer to keep the switches the same.

SET is primarily designed for environments where LACP is not a requirement. If you need to use SET, you might need to configure your switches to use a different mode that is compatible with SET, such as Switch Independent mode.

If LBFO is critical for your setup, reinstalling the server with Windows Server 2022 might be the best option.

Do bear in mind as you progress in years, SET Will be the way forward, it makes sense to invest in changes to the network now, rather than when you’re forced, if you can.

Years ago we used switch independent mode. but due to bad performance we changed everything to LACP. so it doesn’t make sense to go back to switch independent.

If someone has a great solution, that would be nice otherwise i will wipe the server on monday and start agin. (we will forward the problem to 2031 in the hope it is solved by then)

1 Spice up

I would think there would be some slight differences of NICs to be assigned to vSwitches for Server 20xx with Hyper-v role VS. ESXi & Hyper-V 20xx (max is 2019 if I am not wrong)…

For Hyper-v Servers and ESXi, we would add NICs to vSwitches, setting them as active instead of standby and the vSwitch would handle the load balancing.
But for Server 20xx with hyper-v role, the host OS first controls the NICs then it is assigned to the “dumb” vSwitch which is literally a virtual NIC (if I remember correctly) then you need to activate cmdline switches to activate the required features.
In Server 2012 with hyper-v role, there was a workaround to first team a few NICs into a single NIC (1 IP address only) but somehow in Server 2022 (or later), you cannot make a NIC team with same type of NICs (I cannot remember the error).