Floating License Three-server Redundancy Cluster
SpinFire Insight - Three-server redundancy cluster (Failover)
A three-server redundancy cluster ensures continuous availability of SpinFire Ultimate floating licenses, even in the event of a server failure. This setup consists of three interconnected license servers—Primary, Secondary, and Tertiary—that communicate over TCP/IP to maintain a quorum-based system for license distribution.
How It Works
Quorum-Based Operation: Licenses remain available as long as at least two of the three servers are active and communicating.
Master Server Role: The Primary server typically functions as the master, managing license distribution. If the Primary server becomes unavailable, the Secondary server assumes the master role, provided the Tertiary server is active.
Heartbeat Communication: The servers exchange heartbeat messages at regular intervals. If a server does not receive a heartbeat from another, it shuts down its vendor daemon to prevent incorrect license allocation.
Triad Redundant Server Constellation

Failover Process: If the Master server (Primary or Secondary) fails, the Master role is automatically transferred to the remaining active server. The new Master takes over license management for SpinFire.
Triad Redundant Server Backup Failover

Providing Information for Redundant Licensing
To set up a three-server redundancy cluster, customers must provide Tech Soft 3D Support with the following details for all three servers:
Server names (hostnames) of all three servers
MAC addresses (HostIDs) of each server
Port number to be used (e.g., 27000)
Once this information is received, Tech Soft 3D Support will generate a redundant license file configured specifically for your environment and send the license to the customer administrator to configure to their license server.
License File Configuration Details
While the configuration is handled internally, the following parameters are used in the SERVER lines of the license file and are important for understanding how the cluster operates:
SERVER Line Format
SERVER [hostname] [hostid] [port] [PRIMARY_IS_MASTER] [HEARTBEAT_INTERVAL=seconds]
PORT
Specifies the port number used for communication between the license servers.
Unlike single-server configurations, each SERVER line in a triad must include a port number.
The port must be a value between 1024 and 64000, ensuring it is not used by any other process.
The default port is 27000, but this can be changed after the license file has been signed.
PRIMARY_IS_MASTER (Optional)
Determines how the Master role is transferred between the Primary and Secondary servers in the triad.
If set, the Primary server will always reclaim the Master role when it comes back online after a failure.
If not set, the Secondary server retains the Master role even after the Primary recovers. The Primary can only become Master again if the Secondary fails.
HEARTBEAT_INTERVAL (Optional)
Defines how long a license server waits for a heartbeat from another license server before shutting itself down.
Valid range: 0–120 seconds
If not specified, the default timeout is 79 seconds (with a base interval of 20 seconds).
Valid values for direct configuration are 0–30 seconds.
Important Considerations
At least two servers must be operational for license distribution to function properly.
All three servers must use the same port number for seamless communication.
Network stability is critical to avoid unnecessary failovers due to missed heartbeat signals.
Do not modify the license file, as any changes to HostID values will invalidate the licenses.
If a server needs to be restarted, all three servers should be restarted in sequence (Primary → Secondary → Tertiary) to maintain quorum.
Note: None of the options file keywords affect three-server redundancy.
By providing the required server details and following these best practices, your organization can ensure high availability and fault tolerance for SpinFire Ultimate floating licenses, minimizing downtime and maintaining seamless access to critical applications.