int startPeerLocation() throws IOException {
    if (isPeerLocator()) {
      throw new IllegalStateException(
          String.format("Peer location is already running for %s", this));
    }
    logger.info("Starting peer location for {}", this);

    peerLocator = true;
    return membershipLocator.start();
  }
Start peer location in this locator. If you plan on starting a distributed system later, this
method should be called first so that the distributed system can use this locator.

@return returns the port that the locator to which the locator is bound
@since GemFire 5.7
geode-core/src/main/java/org/apache/geode/distributed/internal/InternalLocator.java