diff --git a/zookeeper-server/src/main/java/org/apache/zookeeper/server/command/RuokCommand.java b/zookeeper-server/src/main/java/org/apache/zookeeper/server/command/RuokCommand.java
index 02bcc803cc4..17463e3a0a0 100644
--- a/zookeeper-server/src/main/java/org/apache/zookeeper/server/command/RuokCommand.java
+++ b/zookeeper-server/src/main/java/org/apache/zookeeper/server/command/RuokCommand.java
@@ -29,7 +29,11 @@ public RuokCommand(PrintWriter pw, ServerCnxn serverCnxn) {
 
     @Override
     public void commandRun() {
-        pw.print("imok");
+        if (!isZKServerRunning()) {
+            pw.println(ZK_NOT_SERVING);
+        } else {
+            pw.print("imok");
+        }
     }
 
 }