diff --git a/hadoop-yarn-project/CHANGES.txt b/hadoop-yarn-project/CHANGES.txt
index 7117fbdd68..fdf13beab4 100644
--- a/hadoop-yarn-project/CHANGES.txt
+++ b/hadoop-yarn-project/CHANGES.txt
@@ -287,6 +287,9 @@ Release 2.7.0 - UNRELEASED
     YARN-3158. Correct log messages in ResourceTrackerService.
     (Varun Saxena via xgong)
 
+    YARN-3179. Update use of Iterator to Iterable in RMAdminCLI and
+    CommonNodeLabelsManager. (Ray Chiang via xgong)
+
   OPTIMIZATIONS
 
     YARN-2990. FairScheduler's delay-scheduling always waits for node-local and 
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/RMAdminCLI.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/RMAdminCLI.java
index af83102c96..d29f674131 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/RMAdminCLI.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/main/java/org/apache/hadoop/yarn/client/cli/RMAdminCLI.java
@@ -128,12 +128,12 @@ public RMAdminCLI(Configuration conf) {
   }
 
   private static void appendHAUsage(final StringBuilder usageBuilder) {
-    for (String cmdKey : USAGE.keySet()) {
-      if (cmdKey.equals("-help")) {
+    for (Map.Entry<String,UsageInfo> cmdEntry : USAGE.entrySet()) {
+      if (cmdEntry.getKey().equals("-help")) {
         continue;
       }
-      UsageInfo usageInfo = USAGE.get(cmdKey);
-      usageBuilder.append(" [" + cmdKey + " " + usageInfo.args + "]");
+      UsageInfo usageInfo = cmdEntry.getValue();
+      usageBuilder.append(" [" + cmdEntry.getKey() + " " + usageInfo.args + "]");
     }
   }
 
@@ -173,14 +173,15 @@ private static void buildIndividualUsageMsg(String cmd,
   private static void buildUsageMsg(StringBuilder builder,
       boolean isHAEnabled) {
     builder.append("Usage: yarn rmadmin\n");
-    for (String cmdKey : ADMIN_USAGE.keySet()) {
-      UsageInfo usageInfo = ADMIN_USAGE.get(cmdKey);
-      builder.append("   " + cmdKey + " " + usageInfo.args + "\n");
+    for (Map.Entry<String,UsageInfo> cmdEntry : ADMIN_USAGE.entrySet()) {
+      UsageInfo usageInfo = cmdEntry.getValue();
+      builder.append("   " + cmdEntry.getKey() + " " + usageInfo.args + "\n");
     }
     if (isHAEnabled) {
-      for (String cmdKey : USAGE.keySet()) {
+      for (Map.Entry<String,UsageInfo> cmdEntry : USAGE.entrySet()) {
+        String cmdKey = cmdEntry.getKey();
         if (!cmdKey.equals("-help")) {
-          UsageInfo usageInfo = USAGE.get(cmdKey);
+          UsageInfo usageInfo = cmdEntry.getValue();
           builder.append("   " + cmdKey + " " + usageInfo.args + "\n");
         }
       }
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/nodelabels/CommonNodeLabelsManager.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/nodelabels/CommonNodeLabelsManager.java
index 25ff417320..cb6f1f3914 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/nodelabels/CommonNodeLabelsManager.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/nodelabels/CommonNodeLabelsManager.java
@@ -383,8 +383,8 @@ protected void checkRemoveFromClusterNodeLabels(
   @SuppressWarnings("unchecked")
   protected void internalRemoveFromClusterNodeLabels(Collection<String> labelsToRemove) {
     // remove labels from nodes
-    for (String nodeName : nodeCollections.keySet()) {
-      Host host = nodeCollections.get(nodeName);
+    for (Map.Entry<String,Host> nodeEntry : nodeCollections.entrySet()) {
+      Host host = nodeEntry.getValue();
       if (null != host) {
         host.labels.removeAll(labelsToRemove);
         for (Node nm : host.nms.values()) {