Access using the IP address of the real adapters

Individual interfaces are still accessible to other systems after VIPA is implemented. However, using the real IP addresses for ping and telnet sessions sidesteps the VIPA advantage of communicating independent of the physical adapters. VIPA hides physical adapter failures from the outlying clients. Using the real addresses reintroduces the dependency upon the physical adapters.

If the remote system contacts the VIPA system using the VIPA address or if an application on the VIPA system initiates the communication to another system, the VIPA address will be used as the source IP address in the packet. However, if the remote system initiates the session using the IP address of the real interface, that real IP address will be the source IP address in the responding packets. There is one exception. For applications that bind to a particular IP interface, the outgoing packets will carry the source address of the interface to which they are bound.