/**
 * Client Registration
 *
 * Handles auto-registration with a main server when this server
 * is started as a client/peer in a cluster.
 */
declare class ClientRegistration {
    private config;
    private heartbeatInterval;
    private registrationRetryTimeout;
    private registered;
    private serverId;
    /**
     * The local IP on the interface that ROUTES TO the main server, learned by
     * opening a TCP connection to it. Registering os.hostname() broke on
     * clusters where compute nodes report an FQDN the controller cannot
     * resolve (cri22cn416.cri.uchicago.edu vs the resolvable cri22cn416):
     * every controller→node fetch died as 500 "fetch failed" while heartbeats
     * (outbound) kept the allocation looking healthy. An IP needs no DNS at
     * all, and the interface that reaches the controller is the one the
     * controller can reach back on.
     */
    private routableLocalAddress;
    /**
     * Initialize client registration from environment variables
     */
    initFromEnv(localPort: number): Promise<void>;
    /**
     * Register with the main server
     */
    private register;
    /**
     * Start heartbeat interval
     */
    private startHeartbeat;
    /**
     * Send heartbeat to main server
     */
    private sendHeartbeat;
    /**
     * Unregister from main server (called on shutdown)
     */
    shutdown(): Promise<void>;
    /**
     * Check if we're running as a client (registered with main server)
     */
    isClient(): boolean;
    /**
     * Get main server URL (if we're a client)
     */
    getMainServerUrl(): string | null;
}
export declare const clientRegistration: ClientRegistration;
export {};