VM network access fails without "Allow management operating system to share this network adapter" checked
- I have a four node Hyper-V cluster in production on Server 2008 in a blade chassis, and a separate two node Hyper-V cluster running Server 2008 R2 on disparate servers. Prior to upgrading our four-node cluster, I have built a two-node development Hyper-V R2 cluster on the blades.
On both of my Hyper-V R2 clusters, I am unable to get virtual machines to connect to any virtual networks unless "Allow management operating system to share this network adapter" is checked on the virtual network. I've tried removing then recreating the virtual network, to no avail.
I'm having this problem both for virtual networks that are VLAN tagged, and for those that have no VLAN tagging. On one of these development node, I have completely disabled (as far as I'm aware) any TCP Offloading at the NIC level. On the other development node, I have left TCP Offloading enabled. I see no change in behavior regardless of offload settings.
This is happening on Dell PowerEdge servers using Intel-based NICs, as well as on our HP Blade chassis using Broadcom NICs with HP drivers. This has me thinking that this probably isn't a hardware issue, though anything is on the table at this point.
I see no major drawbacks to enabling host-level access to virtual networks, however my preference would be to take advantage of the new R2 functionality instead of disabling the IP stacks on the host-level virtual NICs to prevent them from occupying DHCP addreses.
Answers
Hi,
Did you mean if you uncheck the "Allow management operating system to share this network adapter" when you created an External Virtual Network bound to one physical NIC. The VMs connected to this External Virtual Network will fail.
If so, please help me to collect the following information:
1. What did you mean by “fails” in “VM network access fails without……”?
2. What did you mean by “I am unable to get virtual machines to connect to any virtual networks unless……”? Please provide more information about the symptom, if there are any error occurred, please provide the details.
By the way, please insert a additional NIC to the computer to test whether you get the same issue.
Vincent Hu
- Marked As Answer byVincent HuMSFT, ModeratorTuesday, October 13, 2009 3:10 AM
- Proposed As Answer byBrian Borg Sunday, October 11, 2009 1:18 AM
All Replies
- If you only have one NIC on each host server, you will have to leave "Allow management operating system to share this network adapter" checked.
Otherwise you will not be able to manage the host. Hi,
Did you mean if you uncheck the "Allow management operating system to share this network adapter" when you created an External Virtual Network bound to one physical NIC. The VMs connected to this External Virtual Network will fail.
If so, please help me to collect the following information:
1. What did you mean by “fails” in “VM network access fails without……”?
2. What did you mean by “I am unable to get virtual machines to connect to any virtual networks unless……”? Please provide more information about the symptom, if there are any error occurred, please provide the details.
By the way, please insert a additional NIC to the computer to test whether you get the same issue.
Vincent Hu
- Marked As Answer byVincent HuMSFT, ModeratorTuesday, October 13, 2009 3:10 AM
- Proposed As Answer byBrian Borg Sunday, October 11, 2009 1:18 AM
· Hi,
Have you tried the suggestion? I want to see if the information provided was helpful. Your feedback is very useful for the further research. Please feel free to let me know if you have addition questions.
Best regards,
Vincent Hu
