FlexLM

FlexLM, also known as FlexNet Publisher, is a commercial software license manager developed by Flexera Software. It is widely used by software vendors to protect their intellectual property and control the usage of their applications. FlexLM operates by issuing and managing license keys that allow users to run specific software products. These licenses can be configured in various ways, including network-based licenses that allow a pool of users to share a limited number of copies of the software, and node-locked licenses that are tied to a specific machine.

The core components of FlexLM are the license server and license client. The license server, often referred to as the "lmgrd" process, is responsible for managing the available licenses and distributing them to clients upon request. The client application, when launched, communicates with the license server to check out a license. If a license is available, it is granted to the client, allowing the software to run. If all licenses are in use, the client will typically display a message indicating that no licenses are available and may prompt the user to try again later.

FlexLM offers several licensing models, such as perpetual licenses, term-based licenses, and concurrent user licenses. This flexibility allows software vendors to tailor their licensing strategies to meet different market needs and customer preferences. Features like license borrowing, where users can temporarily take a license offline for use away from the network, are also supported. For administrators, FlexLM provides tools for monitoring license usage, managing license servers, and generating reports on software utilization. This helps in understanding software return on investment and optimizing license allocation.