What are redundant license servers and how do they work?
This configuration is optional. Redundant servers are a “team” of three FLEXlm-based license servers that operate together to serve a single pool of license keys. For example, you could configure servers A, B and C as redundant servers to serve 100 ClearQuest and Suite license keys. Servers A, B and C will work together to manage the keys. If one of the license servers becomes inoperable, the other two servers will seamlessly continue to serve your 100 keys.
This configuration is optional. Redundant servers are a set of 3 nodes designated to serve the same license file. The license file has 3 SERVER lines. lmgrd is started on all 3 nodes. One of the servers starts out as the master server and serves licenses. If the master goes down, another server takes over as master. Redundant servers require a quorum of 2 servers to be up, or no licenses are served. All the three servers should have stable network communication between themselves. These three-server redundant servers should have excellent communications. This form of redundancy requires that the servers exchange heartbeats periodically, and poor communications can cause poor performance. You should never configure redundant servers with slow communications or dialup links. In all cases, an effort should be made to select stable systems as server nodes; in other words, do not pick systems that are frequently rebooted or shut down for one reason or another. The three server nodes can be
