diff --git a/shell/src/main/java/org/apache/zeppelin/shell/ShellInterpreter.java b/shell/src/main/java/org/apache/zeppelin/shell/ShellInterpreter.java
index 5914236aee..1ac25f3599 100644
--- a/shell/src/main/java/org/apache/zeppelin/shell/ShellInterpreter.java
+++ b/shell/src/main/java/org/apache/zeppelin/shell/ShellInterpreter.java
@@ -71,7 +71,11 @@ public class ShellInterpreter extends KerberosInterpreter {
     for (String executorKey : executors.keySet()) {
       DefaultExecutor executor = executors.remove(executorKey);
       if (executor != null) {
-        executor.getWatchdog().destroyProcess();
+        try {
+          executor.getWatchdog().destroyProcess();
+        } catch (Exception e){
+          LOGGER.error("error destroying executor for paragraphId: " + executorKey, e);
+        }
       }
     }
   }
@@ -126,7 +130,11 @@ public class ShellInterpreter extends KerberosInterpreter {
   public void cancel(InterpreterContext context) {
     DefaultExecutor executor = executors.remove(context.getParagraphId());
     if (executor != null) {
-      executor.getWatchdog().destroyProcess();
+      try {
+        executor.getWatchdog().destroyProcess();
+      } catch (Exception e){
+        LOGGER.error("error destroying executor for paragraphId: " + context.getParagraphId(), e);
+      }
     }
   }
 
@@ -157,6 +165,7 @@ public class ShellInterpreter extends KerberosInterpreter {
     try {
       ShellSecurityImpl.createSecureConfiguration(getProperty(), shell);
     } catch (Exception e) {
+      LOGGER.error("Unable to run kinit for zeppelin", e);
       return false;
     }
     return true;
diff --git a/zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/KerberosInterpreter.java b/zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/KerberosInterpreter.java
index 51ae617fe6..8984f28aec 100644
--- a/zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/KerberosInterpreter.java
+++ b/zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/KerberosInterpreter.java
@@ -31,10 +31,6 @@ import org.slf4j.LoggerFactory;
 /**
  * Interpreter wrapper for Kerberos initialization
  *
- * TODO: coming soon
- * Please see,
- * https://zeppelin.apache.org/docs/latest/development/writingzeppelininterpreter.html
- *
  * runKerberosLogin() method you need to implement that determine Zeppelin's behavior.
  * startKerberosLoginThread() needs to be called inside the open() and
  * shutdownExecutorService() inside close().
@@ -101,8 +97,11 @@ public abstract class KerberosInterpreter extends Interpreter {
           scheduledExecutorService
               .schedule(this, getTimeAsMs(getKerberosRefreshInterval()), TimeUnit.MILLISECONDS);
         } else {
+          kinitFailCount++;
+          logger.info("runKerberosLogin failed for   " + kinitFailCount + "time");
           // schedule another retry at once or close the interpreter if too many times kinit fails
           if (kinitFailCount >= kinitFailThreshold()) {
+            logger.error("runKerberosLogin failed for  max attempts, calling close interpreter.");
             close();
           } else {
             scheduledExecutorService.submit(this);