public static int hashCodeMemberId(byte[] memberID) {
    if (memberID.length < (NULL_90_MEMBER_DATA_LENGTH + MINIMUM_ID_LENGTH)
        || !nullUUIDCheck(memberID, memberID.length - NULL_90_MEMBER_DATA_LENGTH)) {
      return Arrays.hashCode(memberID);
    }
    byte[] newID = new byte[memberID.length - NULL_90_MEMBER_DATA_LENGTH];
    System.arraycopy(memberID, 0, newID, 0, newID.length);
    return Arrays.hashCode(newID);
  }
form the hashcode for the memberID byte array
geode-core/src/main/java/org/apache/geode/internal/cache/EventID.java