diff --git a/spark/src/main/java/org/apache/zeppelin/spark/ZeppelinR.java b/spark/src/main/java/org/apache/zeppelin/spark/ZeppelinR.java
index 26488337b11..961793db17e 100644
--- a/spark/src/main/java/org/apache/zeppelin/spark/ZeppelinR.java
+++ b/spark/src/main/java/org/apache/zeppelin/spark/ZeppelinR.java
@@ -141,6 +141,9 @@ public void open() throws IOException {
     cmd.addArgument(Integer.toString(port));
     cmd.addArgument(libPath);
     cmd.addArgument(Integer.toString(sparkVersion.toNumber()));
+    
+    // dump out the R command to facilitate manually running it, e.g. for fault diagnosis purposes
+    logger.debug(cmd.toString());
 
     executor = new DefaultExecutor();
     outputStream = new SparkOutputStream(logger);