Throughout this document, we use the term "three-server network" when referring to redundant triad servers. Redundant server setup is a network configuration where multiple machines are designated as license servers. Redundancy can be achieved in two ways:
Any number of license server machines can be running independently. The total number of licenses is split between each license server. For example, if you are licensed for 20 tasks of a certain product, and you have two license server machines, each license server machine will serve ten licenses. In this example, if one of these machines fails, only ten licenses will be available.
Three different machines can be selected to work together in tandem (typically referred to as a redundant triad), where two of the three must be running at all times. These three license server machines work from a single set of licenses. This option is not recommended.
Caution: If you are running redundant servers, you should have the license file (as well as the entire licensing directory) installed locally on each license server. If you do not, you lose all the advantages of having redundant servers, since the file server holding these files becomes a single point of failure.
We recommend using multiple independent license server machines to achieve redundancy; however, if your site requires the use of three license server machines working in tandem, follow the guidelines in this section to configure the servers.
Install the License Manager on each of the three servers as described in Installing the License Manager. Be sure that each machine meets all of the prerequisites.
Start each of the license servers using the same license file on each machine. The license file for the three-server setup will begin with three SERVER lines:
SERVER myserver1 00e2463 1055 SERVER myserver2 00132460b724 1055 SERVER myserver3 001a246d4e64 1055 The first SERVER line is the license server you have designated as the primary server followed by the second and third servers, which act as the backup servers.
Always start the primary server first. If not, the second or third server will take over as the master server.
When you start each license server, you will see a message indicating that the server is starting. The primary server will not be fully started until you start the second or third server, creating a quorum. Until you have a quorum of servers started, the Ansys License Management Center will show the Licensing Interconnect and monitor running while FlexNet will show as not running. You could see a delay of up to five minutes in the startup of a server's FlexNet component while the communication between all three servers is being established. If a connection cannot be established within the five minutes, the Licensing Interconnect and Licensing Interconnect Monitor will stop. Check the Ansys License Management Center to verify that all components have stopped before you attempt to restart the Ansys License Manager on any server.
To stop redundant servers, use the option of the Ansys License Management Center to manually stop the License Manager on each server. The option stops only the "local" instance of the License Manager, therefore it is necessary for you to stop each instance individually.