The virtual switch selects an uplink for a virtual machine based on the virtual machine MAC address. To calculate an uplink for a virtual machine, the virtual switch uses the virtual machine MAC address and the number of uplinks in the NIC team.

Table 1. Considerations on Using Route Based on Source MAC Hash

Considerations

Description

Advantages

  • A more even distribution of the traffic than Route Based on Originating Virtual Port, because the virtual switch calculates an uplink for every packet.

  • Virtual machines use the same uplink because the MAC address is static. Powering a virtual machine on or off does not change the uplink that the virtual machine uses.

  • No changes on the physical switch are required.

Disadvantages

  • The bandwidth that is available to a virtual machine is limited to the speed of the uplink that is associated with the relevant port ID, unless the virtual machine uses multiple source MAC addresses.

  • Higher resource consumption than Route Based on Originating Virtual Port, because the virtual switch calculates an uplink for every packet.

  • The virtual switch is not aware of the load of the uplinks, so uplinks might become overloaded.