What is Multi-Homing?

A computer on the network may have multiple network cards, and each network card represents an interface to the computer. Of course, this computer also has multiple physical addresses. Such a computer is called a multihomed computer.

The mode of connecting to the backbone network through only one link is prone to a single point of failure.

Multihomed computers contain multiple network interface cards (NICs) and intervene on multiple networks simultaneously. For example, a Windows NT Server can contain two network cards, one of which

Computers can be multihomed for the following reasons:
(1) Scalability. If the server requires more throughput than a single interface allows, then you can use two network adapters to double the maximum throughput (assuming the server hardware supports network adapter teaming). For example, if the streaming media service is connected on a Gigabit network and requires a transmission rate of 1.2Gbps, then two network adapters can be connected to achieve a theoretical outbound throughput rate close to 2Gbps.
(2) Redundancy. In order to avoid a server outage caused by a network adapter failure, you can configure redundant network adapters. When one network adapter fails, the other network adapter continues to maintain connectivity. You can then schedule a server downtime with minimal impact to the user to replace the failed wind network adapter.
(3) Connect separate networks. Some servers need to be connected to multiple separate networks (disconnected networks). For example, the update server connects to an internal network to allow clients to download updates, and it needs to connect to a separate laboratory network so that computers in the laboratory can download updates. When connecting to separate networks, configure the default gateway on only one adapter. If you need to connect to multiple networks through this separate network, you can use the route add command to manually configure the computer's routing table. ^[1]