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A newly created virtual switch disappears after you restart


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Symptoms

Consider the following scenario:
  • You configure Windows Server 2012 or Windows Server 2012 R2 to start from an iSCSI boot disk over a network adapter.
  • The Hyper-V role is installed on the server, and a virtual switch is created on an external network adapter that is not involved in the iSCSI boot process.
After you restart, the new virtual switch appears in the Hyper-V Virtual Switch Manager as Internal network and is no longer associated with the network adapter. If you try to remove the virtual switch, the removal fails, and you receive the following error message:

Error applying Virtual Switch Properties changes. Failed while removing the virtual Ethernet switch.

If you view the Network connections area for the Hyper-V host, the virtual switch does not appear.

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Cause

The Hyper-V virtual switch is not supported when you start Windows Server 2012 or Windows Server 2012 R2 from an iSCSI boot disk. This is true even when the external network adapter is not involved in the iSCSI boot feature.

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Resolution

This issue is fixed in Windows Server 2016 and later versions. In Windows Server 2012 or Windows Server 2012 R2, to remove the virtual switch and its association with the external network adapter, remove the Hyper-V role.

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Keywords: kbexpertiseadvanced, kbsurveynew, kbtshoot, kb

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Article Info
Article ID : 2969306
Revision : 1
Created on : 1/7/2017
Published on : 8/11/2016
Exists online : False
Views : 285