When upgrading a vCenter Server appliance with two or more network interface cards (NICs), the upgrade transfers the IP addresses from each network interface from the source vCenter Server to the target vCenter Server.

During the upgrade process, the Upgrade installer performs a pre-check of the source vCenter Server and records the network settings. When this information is transferred to the target vCenter Server appliance, the network settings are transferred as part of the configuration. When the upgrade process finishes, you can log in to the vCenter Server appliance using the vSphere ClientvSphere Client, and verify that the IP addresses have been successfully transferred to the newly upgraded vCenter Server appliance.

With two or more NICs per vCenter Server appliance, you can better manage network traffic in your environment. For example, with multiple network interfaces you can:
  • Configure backup traffic to use a different network than management traffic.
  • Keep ESXi hosts on a physically different LAN segment from your management traffic. You can connect one network interface to the network with your ESXi hosts, and connect the other to a network from which administrative clients connect to vCenter Server.