When you perform a live migration of a Hyper-V virtual machine on Windows Server 2008 R2, the live migration may fail and the virtual machine will have a status of Online (Migration attempt failed).
On the destination node, the following events will be logged in the Microsoft-Windows-Hyper-V-High-Availability/Admin event log:
Log Name: Microsoft-Windows-Hyper-V-High-Availability-Admin
Source: Microsoft-Windows-Hyper-V-High-Availability
Event ID: 21203
Description:
Failed to create virtual network switch port '4825deff-6f69-45fd-92f2-3d344f0b95b2'. (HRESULT 0x80070490)
Log Name: Microsoft-Windows-Hyper-V-High-Availability-Admin
Source: Microsoft-Windows-Hyper-V-High-Availability
Event ID: 21125
Description:
Configuration setup for live migration failed on the destination node. Make sure that name of the virtual network is the same on the source and destination nodes, and try the live migration again.
On the destination node, the following events will be logged in the Microsoft-Windows-Hyper-V-High-Availability/Admin event log:
Log Name: Microsoft-Windows-Hyper-V-High-Availability-Admin
Source: Microsoft-Windows-Hyper-V-High-Availability
Event ID: 21203
Description:
Failed to create virtual network switch port '4825deff-6f69-45fd-92f2-3d344f0b95b2'. (HRESULT 0x80070490)
Log Name: Microsoft-Windows-Hyper-V-High-Availability-Admin
Source: Microsoft-Windows-Hyper-V-High-Availability
Event ID: 21125
Description:
Configuration setup for live migration failed on the destination node. Make sure that name of the virtual network is the same on the source and destination nodes, and try the live migration again.