Solve network connection problems caused by external vswitches

Solve network connection problems caused by external vswitches

Nirmal Sharma is an expert in the activity directory Field and has obtained Microsoft MCSEx3, mcui, and MVP certification. He would like to share some related knowledge with you. Here I have compiled an article on how to solve the network connection problems arising from using the Hyper-V External virtual network switch.

Microsoft Hyper-V provides three types of virtual network switches: Internal, private, and external. These vswitches are created using the Hyper-V Switch manager.

Internal vswitches allow communication between virtual machines to connect internal vswitches and Hyper-V hosts. If you want to restrict communication between virtual machines to the same vswitch, you can use a Windows Server TutorialsA vswitch.

The external vswitch allows the virtual machine to communicate with the enterprise LAN. An external virtual network switch requires a physical network adapter installed on the Hyper-V host to communicate with the enterprise LAN.

External vswitches are mapped to physical network adapters. Private and internal vswitches can be created without being mapped to a physical network adapter.

Many virtual administrators do not know that when an external virtual network switch is created, the data flow on the Hyper-V host changes. By default, the Windows server operating system uses a physical network adapter to send network packets. This is because the physical network adapter required by the network service must be bound with the network protocol and service.

When an external virtual network switch is created, all network packets are generated by the network services/applications received by the switch. Once an external vswitch receives network packets, these packets are forwarded to the mapped physical network adapter.

This is because when you create an external vswitch, The vswitch manager modifies some necessary properties of the physical network adapter and external vswitch. Before the vswitch manager implements the change, you should see a warning message shown on the following screen:

External vswitch warning

Warning Hyper-V host connection failed. This warning is not displayed when you create a private or internal vswitch. The above prompt is displayed only when an external vswitch is created. This is because the changes are handled during the creation process, including the binding and unbinding of protocols, services, and customer services.

For example, you have created an external virtual Network switch named "ExtSwitch" and mapped it to a physical Network adapter named "Intel (R) 82576 Gigabit Dual Port Network. When you click "Apply", the attributes of the physical network adapter change as follows:

● Unbind the following services, protocols and customers: Microsoft network client, Microsoft network file and printer sharing, TCP/IP IPv4, TCP/IP IPv6, and all other services, clients, or protocols listed in the physical network adapter properties.

● Bind the "Microsoft vswitch protocol ".

In addition, in ExtSwitch, the following changes occur to the external virtual network switch:

● Bind the following services, protocols, and clients: Microsoft network client, Microsoft network file and printer sharing, TCP/IP IPv4, and TCP/IP IPv6.

● Unbind the "Microsoft vswitch protocol ".

In this process, a new network connection is created in the network connection folder, and the name is specified when an external virtual network switch (ExtSwitch) is created.

The "Microsoft vswitch protocol" is bound to a physical network adapter and monitors network traffic from external vswitches. If the "Microsoft vswitch protocol" is not bound to a physical network adapter, the physical network adapter will reduce the network packets generated by the external virtual network switch.

The entire process cancels the protocols, services, and clients from the memory, and ends all network meetings in the system where the physical network adapter is located. When a virtual network is created, the following connections are established:

● All virtual machines using RDP are connected.

● All virtual machine connection tools or vmconnect.exe Virtual Machine connections are used.

● Any other network is connected to the hyper-v host or virtual machine.

● Use a physical network adapter to connect to all network connections of the Hyper-V host or virtual machine.

We recommend that you plan the downtime when creating an external vswitch on the Hyper-V host.