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The miniport 'Microsoft Virtual Machine Bus Network Adapter' disconnected.

Question
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Hi, I have two HP DL380's each running Server 2008 R2 and the Hyper-V role. Each Hyper-V server has a single VM which is also running Server 2008 R2 (the two VM's are nodes in an SQL cluster). Today I noticed the SQL service had failed across from Node1 to Node2, looking in the System Event Log I noticed the nics on Node1 had disconnected with the following error-
The miniport 'Microsoft Virtual Machine Bus Network Adapter' disconnected.
This is then followed by the other three nics on the node disconnecting. After 3 minutes the disconnected nics will reconnect however by that time the system has failed over to Node2. Looking in the Event Logs on the physical host server I'm not seeing any network connectivity errors during the period the virtual Node is having issues..
The Event ID is 9 and the source is NETVSC
I noticed there is a patch for a similar issue available for people seeing their adapters "hang" when hosting Windows 2003 VM's but it's not quite the same situation for us, our nodes are "disconnecting" and the O/S is 2008 R2. Both nodes have the Hyper-V integration services installed. Any advice would be greatly appreciated.
Thanks,
Adam.
Answers
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Hi Adam,
I would recommend is making sure you have the latest networking drivers installed for the hardware you are using in the parent partition.
Similar threads
http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/8667aed0-e749-4ef6-a8c6-ba516ead7985/
- Marked as answer by Vincent HuModerator Monday, December 13, 2010 2:48 AM
All replies
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Hi.
Remember that R2 have a feature known as core parking where in the cpu go to a lower power state. This has caused som issues in Hyper-V / VM.
Try to change the power state of the CPU (control panel->power options-> change the settings from balanced to high performance under 'Power plan'
Kristian (Virtualization and some coffee: http://kristiannese.blogspot.com ) -
Please check
http://support.microsoft.com/kb/974909
Consider the following scenario:
- You install the Hyper-V role on a computer that is running Windows Server 2008 R2.
- You run a virtual machine on the computer.
- You use a network adapter on the virtual machine to access a network.
- You establish many concurrent network connections, or there is heavy outgoing network traffic.
In this scenario, the network connection on the virtual machine may be lost. Additionally, the network adapter is disabled.
Note You have to restart the virtual machine to recover from this issue.
You have to install this hotfix f or this problem, Now everything is fine
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Hi thanks for the info, I've changed the CPU power settings which I'll monitor for any benefit.
The hotfix I'm not sure fits our exact issue. The adapters disconnect but then auto reconnect 3 minutes later without any intervention. We dont need to re-enable the nic or restart the virtual machine to recover from the issue. Also, it's every nic which gets disconnected (public/private/iscsi), not just the public cluster nic which is the only one I can imagine being under high utilisation.
However, I may install the update if the problem persists just to be sure!
Thanks,
Adam.
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Hi Adam,
I would recommend is making sure you have the latest networking drivers installed for the hardware you are using in the parent partition.
Similar threads
http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/8667aed0-e749-4ef6-a8c6-ba516ead7985/
- Marked as answer by Vincent HuModerator Monday, December 13, 2010 2:48 AM
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Hi All,
I too have same issue, but here my hosts are running with Windows server 2008 R2 and the VM is Windows 2012 R2.
I have total 3 VMs with 2012 R2 running on Windows 2008 R2 cluster. as I noticed only this 3 VMs have NIC disconnect issues, but these are getting connected back with in 3 minutes.
Any help here ?