Q. What are the types of Virtual Switch available in VMware ESX?

A. Like in Hyper-V, you can create different types of Virtual Switch in ESX. These switches are used for network connectivity, but there are different types of services on ESX which Virtual Switches can be provisioned for.

Upstream, a Virtual Switch can be used by a VMkernel Port, Virtual Machine Port or Service Console Port. A VMkernel port is used for iSCSI and NAS based storage communication in addition to VMotion communications. The Service Console port is used for the service console/management operations and the Virtual Machine port is used as part of a virtual machine configuration to give the virtual machine network access.

Downstream, a Virtual Switch can be connected so there are no physical NICS, which means it creates an internal switch. Only VMs on the ESX host can communicate with each other via the switch, as shown here.

If a Virtual Switch is bound to one physical NIC, you get external connectivity. If you connect multiple physical NICs to a Virtual Switch, ESX automatically creates a NIC teamed Virtual Switch, as shown here.

It's possible to have multiple types or ports to the same physical NIC. For example, you could have a Service Console port, VMkernet port and VM port all connected to the same physical NIC. You just need to consider the bottleneck the NIC may become.

Virtual Switches support Virtual LANs (VLANs) which allow connectivity to multiple networks through VLAN tagging. IEEE 802.1Q VLAN tagging is supported. As traffic leaves the Virtual Switch the appropriate VLAN tag is automatically added which is then acted upon by the receiving switch.

Related Reading

Videos:

Audio:

Check out hundreds more useful Q&As like this in John Savill's FAQ for Windows. Also, watch instructional videos made by John at ITTV.net.