private ServerName getMetaLocationOrNull(HMaster master) {
    RegionStateNode rsn = master.getAssignmentManager().getRegionStates()
      .getRegionStateNode(RegionInfoBuilder.FIRST_META_REGIONINFO);
    if (rsn != null) {
      return rsn.isInState(RegionState.State.OPEN) ? rsn.getRegionLocation() : null;
    }
    return null;
  }
The servlet responsible for rendering the index page of the master.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/http/MasterStatusServlet.java