Revert "HBASE-24327 : Flaky connection in TestMasterShutdown#testMasterShutdo… (#1690)"

This reverts commit d9b60d3339.

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestMasterShutdown.java

@@ -22,8 +22,6 @@ import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import java.io.IOException;
 import java.util.List;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CompletionException;
 import java.util.concurrent.TimeUnit;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ClusterMetrics;
@@ -33,6 +31,7 @@ import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.LocalHBaseCluster;
 import org.apache.hadoop.hbase.MiniHBaseCluster;
 import org.apache.hadoop.hbase.StartMiniClusterOption;
+import org.apache.hadoop.hbase.Waiter;
 import org.apache.hadoop.hbase.testclassification.LargeTests;
 import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.util.JVMClusterUtil.MasterThread;
@@ -152,9 +151,7 @@ public class TestMasterShutdown {
       hbaseCluster = new LocalHBaseCluster(htu.getConfiguration(), options.getNumMasters(),
         options.getNumRegionServers(), options.getMasterClass(), options.getRsClass());
       final MasterThread masterThread = hbaseCluster.getMasters().get(0);
-
       masterThread.start();
-      final CompletableFuture<Void> shutdownFuture = CompletableFuture.runAsync(() -> {
       // Switching to master registry exacerbated a race in the master bootstrap that can result
       // in a lost shutdown command (HBASE-8422, HBASE-23836). The race is essentially because
       // the server manager in HMaster is not initialized by the time shutdown() RPC (below) is
@@ -163,35 +160,10 @@ public class TestMasterShutdown {
       // manager is usually init'ed in time for the RPC to be made. For now, adding an explicit
       // wait() in the test, waiting for the server manager to become available.
       final long timeout = TimeUnit.MINUTES.toMillis(10);
-        assertNotEquals("timeout waiting for server manager to become available.", -1,
+      assertNotEquals("Timeout waiting for server manager to become available.",
-          htu.waitFor(timeout, () -> masterThread.getMaster().getServerManager() != null));
+        -1, Waiter.waitFor(htu.getConfiguration(), timeout,
-
+          () -> masterThread.getMaster().getServerManager() != null));
-        // Master has come up far enough that we can terminate it without creating a zombie.
-        LOG.debug("Attempting to establish connection.");
-        try {
-          // HBASE-24327 : (Resolve Flaky connection issues)
-          // shutdown() RPC can have flaky ZK connection issues.
-          // e.g
-          // ERROR [RpcServer.priority.RWQ.Fifo.read.handler=1,queue=1,port=53033]
-          // master.HMaster(2878): ZooKeeper exception trying to set cluster as down in ZK
-          // org.apache.zookeeper.KeeperException$SystemErrorException:
-          // KeeperErrorCode = SystemError
-          //
-          // However, even when above flakes happen, shutdown call does get completed even if
-          // RPC call has failure. Hence, subsequent retries will never succeed as HMaster is
-          // already shutdown. Hence, it can fail. To resolve it, after making one shutdown()
-          // call, we are ignoring IOException.
       htu.getConnection().getAdmin().shutdown();
-          LOG.info("Shutdown RPC sent.");
-        } catch (IOException | CompletionException e) {
-          LOG.warn("Failed to establish connection.", e);
-        } catch (Throwable e) {
-          LOG.warn("Something unexpected happened.", e);
-          throw new RuntimeException(e);
-        }
-      });
-
-      shutdownFuture.join();
       masterThread.join();
     } finally {
       if (hbaseCluster != null) {
@@ -214,9 +186,19 @@ public class TestMasterShutdown {
     conf.setInt(ServerManager.WAIT_ON_REGIONSERVERS_MINTOSTART, 1);
     // don't need a long write pipeline for this test.
     conf.setInt("dfs.replication", 1);
-    // reduce client retries
+    return conf;
-    conf.setInt("hbase.client.retries.number", 3);
+  }
-    // Recoverable ZK configs are tuned more aggressively
+
+  /**
+   * Create a new {@link Configuration} based on {@code baseConf} that has ZooKeeper connection
+   * settings tuned very aggressively. The resulting client is used within a retry loop, so there's
+   * no value in having the client itself do the retries. We want to iterate on the base
+   * configuration because we're waiting for the mini-cluster to start and set it's ZK client port.
+   *
+   * @return a new, configured {@link Configuration} instance.
+   */
+  private static Configuration createResponsiveZkConfig(final Configuration baseConf) {
+    final Configuration conf = HBaseConfiguration.create(baseConf);
     conf.setInt(ReadOnlyZKClient.RECOVERY_RETRY, 3);
     conf.setInt(ReadOnlyZKClient.RECOVERY_RETRY_INTERVAL_MILLIS, 100);
     return conf;