backends.radius.server-selection

server-selection

Selects the server-selection algorithm used when multiple RADIUS server blocks are configured. See Backend Load Balancing for algorithm details, tie-breaking rules, pool-skip behavior, and full examples.

Allowed values

• fallback - Tries servers in priority order (default).
• round-robin - Distributes requests across available servers in rotation.
• hash-balance - Hashes one or more configured AAA context fields to select a stable preferred server.
• least-connections - Routes to the server with the fewest in-use backend sockets (counts backend sockets, not requests already in flight).
• no-fallback - Tries only the highest-priority available server; failures are not retried on other servers.

Default: fallback

Example

radius "EXAMPLE-SERVER" {
    server-selection round-robin;

    server "PRIMARY" {
        secret "mysecret";
        connections { min 1; }
        connect { protocol udp; host "192.168.1.10"; port 1812; }
    }

    server "SECONDARY" {
        secret "mysecret";
        connections { min 1; }
        connect { protocol udp; host "192.168.1.11"; port 1812; }
    }
}