Method markFailedByKey

src/node/runtime/sshConnectionPool.ts:425–443

* Mark connection as failed (internal use after failed probe)

(key: string, error: string)

   * Mark connection as failed (internal use after failed probe)
   */
  private markFailedByKey(key: string, error: string): void {
    const current = this.health.get(key);
    const failures = (current?.consecutiveFailures ?? 0) + 1;
    const backoffIndex = Math.min(failures - 1, SSH_BACKOFF_SCHEDULE_SECONDS.length - 1);
    const backoffSecs = withSshBackoffJitter(SSH_BACKOFF_SCHEDULE_SECONDS[backoffIndex]);

    this.clearReadyControlPaths(key);
    this.health.set(key, {
      status: "unhealthy",
      lastFailure: new Date(),
      lastError: error,
      backoffUntil: new Date(Date.now() + backoffSecs * 1000),
      consecutiveFailures: failures,
    });

    log.warn(
      `SSH connection failed (${failures} consecutive). Backoff for ${backoffSecs.toFixed(1)}s. Error: ${error}`
    );
  }

  /**
   * Clear all health state. Used in tests to reset between test cases