Virtual IP address

A virtual IP address eliminates a host's dependency upon individual network interfaces.

Incoming packets are sent to the system's VIPA address, but all packets travel through the real network interfaces.

Previously, if an interface failed, any connections to that interface were lost. With VIPA on your system and routing protocols within the network providing automatic reroute, recovery from failures occurs without disruption to the existing user connections that are using the virtual interface as long packets can arrive through another physical interface. Systems running VIPA are more highly available because adapter outages no longer affect active connections. Because multiple physical adapters carry the system IP traffic, overall load is not concentrated on a single adapter and associated subnet.

The AIX® VIPA function is transparent to the network equipment. No special network equipment or other hardware is needed. To implement VIPA, you need to have the following items:

two or more existing IP interfaces of any physical type on different subnets that connect into the corporate network
IP routing protocols running within the corporate network