diff --git a/bookkeeper-server/src/main/java/org/apache/bookkeeper/net/NetworkTopologyImpl.java b/bookkeeper-server/src/main/java/org/apache/bookkeeper/net/NetworkTopologyImpl.java
index 123f13ca8a3..19b2c0497f7 100644
--- a/bookkeeper-server/src/main/java/org/apache/bookkeeper/net/NetworkTopologyImpl.java
+++ b/bookkeeper-server/src/main/java/org/apache/bookkeeper/net/NetworkTopologyImpl.java
@@ -17,6 +17,7 @@
  */
 package org.apache.bookkeeper.net;
 
+import com.google.common.base.Strings;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -119,9 +120,10 @@ boolean isRack() {
          * @return true if this node is an ancestor of <i>n</i>
          */
         boolean isAncestor(Node n) {
-            return getPath(this).equals(NodeBase.PATH_SEPARATOR_STR)
+            return !Strings.isNullOrEmpty(n.getNetworkLocation())
+                && (getPath(this).equals(NodeBase.PATH_SEPARATOR_STR)
                     || (n.getNetworkLocation() + NodeBase.PATH_SEPARATOR_STR).startsWith(getPath(this)
-                            + NodeBase.PATH_SEPARATOR_STR);
+                            + NodeBase.PATH_SEPARATOR_STR));
         }
 
         /**
diff --git a/bookkeeper-server/src/test/java/org/apache/bookkeeper/net/NetworkTopologyImplTest.java b/bookkeeper-server/src/test/java/org/apache/bookkeeper/net/NetworkTopologyImplTest.java
index a6cc8c330a3..6122e51f0cd 100644
--- a/bookkeeper-server/src/test/java/org/apache/bookkeeper/net/NetworkTopologyImplTest.java
+++ b/bookkeeper-server/src/test/java/org/apache/bookkeeper/net/NetworkTopologyImplTest.java
@@ -17,7 +17,9 @@
  */
 package org.apache.bookkeeper.net;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import java.util.Set;
 import org.junit.Test;
@@ -97,4 +99,31 @@ public void getLeavesShouldReturnLeavesThatAreNotInExcludedScope() {
       assertTrue(leavesExcludingRack2Scope.contains(bookieRack0ScopeNode));
       assertTrue(leavesExcludingRack2Scope.contains(bookieRack2ScopeNode));
   }
+
+  @Test
+  public void testInvalidRackName() {
+      NetworkTopologyImpl networkTopology = new NetworkTopologyImpl();
+      String rack0Scope = "";
+      BookieId bookieIdScopeRack0 = BookieId.parse("bookieIdScopeRack0");
+      BookieNode bookieRack0ScopeNode = new BookieNode(bookieIdScopeRack0, rack0Scope);
+
+      String rack1Scope = "/";
+      BookieId bookieIdScopeRack1 = BookieId.parse("bookieIdScopeRack1");
+      BookieNode bookieRack1ScopeNode = new BookieNode(bookieIdScopeRack1, rack1Scope);
+
+      try {
+          networkTopology.add(bookieRack0ScopeNode);
+          fail();
+      } catch (IllegalArgumentException e) {
+          assertEquals("bookieIdScopeRack0, which is located at , is not a decendent of /", e.getMessage());
+      }
+
+      try {
+          networkTopology.add(bookieRack1ScopeNode);
+          fail();
+      } catch (IllegalArgumentException e) {
+          assertEquals("bookieIdScopeRack1, which is located at , is not a decendent of /", e.getMessage());
+      }
+
+  }
 }
\ No newline at end of file