What are virtual IP addresses?

Virtual IP addresses are IP addresses that are not tethered to particular machines. Thus, they can rotate among nodes in a Content Gateway cluster.

It is common for a single machine to represent multiple IP addresses on the same subnet. This machine would have a primary or real IP address bound to its interface card and also serve many more virtual addresses.

You can set up your user base to use a DNS round-robin pointing at virtual IP addresses, as opposed to using the real IP addresses of the Content Gateway machines.

Because virtual IP addresses are not bound to machines, a Content Gateway cluster can take addresses from inactive nodes and distribute those addresses among the remaining live nodes.

Using a proprietary management protocol, Content Gateway nodes communicate their status with their peers. If a node fails, its peers notice the failure and negotiate which of the remaining nodes will mask the fault by taking over the failed node’s virtual interface.