AMBARI-20179 : AMS Collector shuts down with Helix-Zk related exception if partial /ambari-metrics-cluster znode exists. (avijayan)
diff --git a/ambari-metrics-timelineservice/src/main/java/org/apache/hadoop/yarn/server/applicationhistoryservice/metrics/timeline/availability/MetricCollectorHAController.java b/ambari-metrics-timelineservice/src/main/java/org/apache/hadoop/yarn/server/applicationhistoryservice/metrics/timeline/availability/MetricCollectorHAController.java
index 12c255e..53e6304 100644
--- a/ambari-metrics-timelineservice/src/main/java/org/apache/hadoop/yarn/server/applicationhistoryservice/metrics/timeline/availability/MetricCollectorHAController.java
+++ b/ambari-metrics-timelineservice/src/main/java/org/apache/hadoop/yarn/server/applicationhistoryservice/metrics/timeline/availability/MetricCollectorHAController.java
@@ -18,6 +18,8 @@
package org.apache.hadoop.yarn.server.applicationhistoryservice.metrics.timeline.availability;
import com.google.common.base.Joiner;
+import org.I0Itec.zkclient.exception.ZkNoNodeException;
+import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
@@ -37,6 +39,7 @@
import org.apache.helix.model.StateModelDefinition;
import org.apache.helix.tools.StateModelConfigGenerator;;
import java.util.ArrayList;
+import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.TreeSet;
@@ -123,8 +126,15 @@
admin.addCluster(clusterName, false);
// Adding host to the cluster
- List<String> nodes = admin.getInstancesInCluster(clusterName);
- if (nodes == null || !nodes.contains(instanceConfig.getInstanceName())) {
+ List<String> nodes = Collections.EMPTY_LIST;
+ try {
+ nodes = admin.getInstancesInCluster(clusterName);
+ } catch (ZkNoNodeException ex) {
+ LOG.warn("Child znode under /" + CLUSTER_NAME + " not found.Recreating the cluster.");
+ admin.addCluster(clusterName, true);
+ }
+
+ if (CollectionUtils.isEmpty(nodes) || !nodes.contains(instanceConfig.getInstanceName())) {
LOG.info("Adding participant instance " + instanceConfig);
admin.addInstance(clusterName, instanceConfig);
}
