private String getReplicatorMetricName(final ReplicatorOptions opts) {
        return "replicator-" + opts.getNode().getGroupId() + "/" + opts.getPeerId();
    }
Send probe or heartbeat request
@param isHeartbeat      if current entries is heartbeat
@param heartBeatClosure heartbeat callback
jraft-core/src/main/java/com/alipay/sofa/jraft/core/Replicator.java