Windows 10: UEFI VM does not network boot anymore after upgrading host from Windows 10 to 11

Hi All,Since I've upgraded my Windows 10 laptop to Windows 11, I've got a strange problem where I hope you can help pointing me in the right direction...On my laptop I have Hyper-v Installed. I have 2 vSwitches, 1 external, 1 private. I also have an MDT/WDS/DHCP/RRAS machine with 2 NIC's in both networks. This machine is the DHCP server on the private vSwitch and is able to hand out IP adresses to VM's already running Windows and Generation 1 VM's that want to boot from network. However, a Gen-2 VM is not able to boot from network and reports "A boot image was not found".When I install Wiresha

:)

 

UEFI VM does not network boot anymore after upgrading host from Windows 10 to 11

Hi All,

Since I've upgraded my Windows 10 laptop to Windows 11, I've got a strange problem where I hope you can help pointing me in the right direction...

On my laptop I have Hyper-v Installed. I have 2 vSwitches, 1 external, 1 private. I also have an MDT/WDS/DHCP/RRAS machine with 2 NIC's in both networks. This machine is the DHCP server on the private vSwitch and is able to hand out IP adresses to VM's already running Windows and Generation 1 VM's that want to boot from network. However, a Gen-2 VM is not able to boot from network and reports "A boot image was not found".

When I install Wireshark on the DHCP VM, I see that other VM's walk through the DHCP sequence normally (Discover-Offer-Request-Ack), but the UEFI VM does not show up (this should show up with a broadcast/discover packet).

When my laptop was running Windows 10, this was all working flawless. After upgrading to Windows 11, this stopped working.

I've already removed Hyper-v and reinstalled the Wifi adapter on the laptop (so all customizations to the Driver settings are reset to default), reinstalled Hyper-v, reconfigured the vSwitches, reconnected the VM's to the vSwitches. This did not resolve the issue.

If you have any clue on where to look or what to check, please let me know!

I'm currently using Windows 11, 22H2 build 25314.1010 (Canary channel)

Kind regards,

Harm

 

Can I share a network connection from a VM to the host OS?

hmm, i will assumer no responces = no, i cannot share it... lucky me, i finally got it to work in 7 with steps pretty close... Program Files > Pantech is where you will need to point windows to inorder to the card running in 7... though it would be nice to be able to share hardware and network connections from a VM to the host PC...

 

Can you allow the host to use the VM network connection?

If you use a VM...

this is possible although not immediately obviously useful. My situation was one where the vm os was able to change settings on a wireless network adapter which allowed me to pick up the signal at a useable strength. The host could not do this. So I was in the weird situation where the vm os - backtrack - had internet but the host - osx 10.6 - did not. Annoying.

Easily corrected as follows:
1. connect the vm to the network, in my case this was wireless so wlan0
2. set up the vm so that is has a local network with the host, make sure the host can ping the vm. In my case this meant enabling eth0 in the vm
3. set up ip forward and iptables masquerade rules on the vm.
4. change the default route of the host to be the vm local ip
5. enjoy the vm network via the host


now I imagine some readers will want more detail on ip forward and masquerade with iptables but there are a lot of tutorials out there for this stuff. It depends on the vm os but if you are using linux then

ip forward with:
$ echo 1 > /proc/sys/net/ipv4/ip_forward

iptables rules something like this
iptables -t nat -A POSTROUTING -s $PRIVATE -o eth0 -j MASQUERADE

{clearly $PRIVATE is your private subnet, set the rules up to run at ifup}

*Smile