There are two possible license server configurations: Single and Redundant.
The single server configuration suits companies where the license server and the mail server are fairly close together on the network or on the same machine. This configuration is the default and the easiest configuration to install and maintain.
A redundant server configuration consists of three servers, acting as one logical server, that manage the same set of license tokens.In this configuration, one of the redundant servers is the master server that issues license tokens and, thus, has a heavier processing load. If the master server becomes unavailable, then the next available peer in the configuration becomes the master server.
Using this configuration should be limited to special situations where its advantages outweigh the increased complexity of installation and maintenance.