@Override
  public UUID getPeerUUID() {
    try {
      AsyncClusterConnection conn = connect();
      String clusterId = FutureUtils
        .get(conn.getAdmin().getClusterMetrics(EnumSet.of(ClusterMetrics.Option.CLUSTER_ID)))
        .getClusterId();
      return UUID.fromString(clusterId);
    } catch (IOException e) {
      LOG.warn("Failed to get cluster id for cluster", e);
      return null;
    }
  }
Some implementations of HBaseInterClusterReplicationEndpoint may require instantiate different
Connection implementations, or initialize it in a different way, so defining createConnection
as protected for possible overridings.
hbase-server/src/main/java/org/apache/hadoop/hbase/replication/HBaseReplicationEndpoint.java