Installation guide

Active/Active
In an active/active configuration with 2 proxies, more than one virtual IP address is
assigned to the virtual IP address pool. At any point in time, one proxy handles the
network traffic that is explicitly directed to it. This deployment is scalable for larger
numbers of proxies.
Clients requesting the IP address of a proxy can be crudely distributed using round
robin DNS. Round robin DNS is not a true load balancing solution, because there is no
way to detect load and redistribute it to a less utilized proxy. Management clustering
should be configured.
An increase in the number of proxy machines makes the use of a PAC file or WPAD
for specifying client configuration instructions convenient. A PAC file may be
modified to adjust for proxy overloads, in a form of load balancing, and to specify
Web site requests that can bypass the proxy.
As with the active/standby configuration, an available proxy can assume a failed
proxy’s load. The following figure illustrates the active/active explicit proxy
configuration: