/**
  * Test adding server to draining servers and then move regions off it. Make sure that no regions
  * are moved back to the draining server.
  *
  * @throws IOException
  * @throws KeeperException
  */
 @Test // (timeout=30000)
 public void testDrainingServerOffloading() throws Exception {
   // I need master in the below.
   HMaster master = TEST_UTIL.getMiniHBaseCluster().getMaster();
   HRegionInfo hriToMoveBack = null;
   // Set first server as draining server.
   HRegionServer drainingServer =
       setDrainingServer(TEST_UTIL.getMiniHBaseCluster().getRegionServer(0));
   try {
     final int regionsOnDrainingServer = drainingServer.getNumberOfOnlineRegions();
     Assert.assertTrue(regionsOnDrainingServer > 0);
     List<HRegionInfo> hris = ProtobufUtil.getOnlineRegions(drainingServer);
     for (HRegionInfo hri : hris) {
       // Pass null and AssignmentManager will chose a random server BUT it
       // should exclude draining servers.
       master.moveRegion(
           null, RequestConverter.buildMoveRegionRequest(hri.getEncodedNameAsBytes(), null));
       // Save off region to move back.
       hriToMoveBack = hri;
     }
     // Wait for regions to come back on line again.
     waitForAllRegionsOnline();
     Assert.assertEquals(0, drainingServer.getNumberOfOnlineRegions());
   } finally {
     unsetDrainingServer(drainingServer);
   }
   // Now we've unset the draining server, we should be able to move a region
   // to what was the draining server.
   master.moveRegion(
       null,
       RequestConverter.buildMoveRegionRequest(
           hriToMoveBack.getEncodedNameAsBytes(),
           Bytes.toBytes(drainingServer.getServerName().toString())));
   // Wait for regions to come back on line again.
   waitForAllRegionsOnline();
   Assert.assertEquals(1, drainingServer.getNumberOfOnlineRegions());
 }