@Override
  public Set<InetAddress> getEquivalents(InetAddress in) {
    Set<InetAddress> result;
    synchronized (equivalentHosts) {
      result = equivalentHosts.get(in);
    }
    // DS 11/25/08 - It appears that when using VPN, the distributed member
    // id is the vpn address, but that doesn't show up in the equivalents.
    if (result == null) {
      result = Collections.singleton(in);
    }
    return result;
  }
Return all of the InetAddress's that are equivalent to the given one (same host)

@param in host to match up
@return all the addresses thus equivalent
geode-core/src/main/java/org/apache/geode/distributed/internal/ClusterDistributionManager.java