diff --git a/jraft-core/src/test/java/com/alipay/sofa/jraft/core/NodeTest.java b/jraft-core/src/test/java/com/alipay/sofa/jraft/core/NodeTest.java
index 2d1ac866e..7e5b4171e 100644
--- a/jraft-core/src/test/java/com/alipay/sofa/jraft/core/NodeTest.java
+++ b/jraft-core/src/test/java/com/alipay/sofa/jraft/core/NodeTest.java
@@ -16,16 +16,6 @@
  */
 package com.alipay.sofa.jraft.core;
 
-import static org.junit.Assert.assertArrayEquals;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNotSame;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
-
 import java.io.File;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
@@ -89,6 +79,16 @@
 import com.alipay.sofa.jraft.util.Utils;
 import com.codahale.metrics.ConsoleReporter;
 
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
 public class NodeTest {
 
     static final Logger         LOG            = LoggerFactory.getLogger(NodeTest.class);
@@ -1002,12 +1002,6 @@ public void testLeaderStopAndReElectWithPriority() throws Exception {
         // stop leader
         assertTrue(cluster.stop(leader.getNodeId().getPeerId().getEndpoint()));
 
-        // apply something when follower
-        final List<Node> followers = cluster.getFollowers();
-        assertFalse(followers.isEmpty());
-
-        sendTestTaskAndWait("follower apply ", followers.get(0), -1);
-
         // elect new leader
         cluster.waitLeader();
         leader = cluster.getLeader();
@@ -1922,11 +1916,14 @@ private void triggerLeaderSnapshot(final TestCluster cluster, final Node leader)
     private void triggerLeaderSnapshot(final TestCluster cluster, final Node leader, final int times)
                                                                                                      throws InterruptedException {
         // trigger leader snapshot
-        assertEquals(times - 1, cluster.getLeaderFsm().getSaveSnapshotTimes());
+        // first snapshot will be triggered randomly
+        int snapshotTimes = cluster.getLeaderFsm().getSaveSnapshotTimes();
+        assertTrue("snapshotTimes=" + snapshotTimes + ", times=" + times, snapshotTimes == times - 1
+                                                                          || snapshotTimes == times);
         final CountDownLatch latch = new CountDownLatch(1);
         leader.snapshot(new ExpectClosure(latch));
         waitLatch(latch);
-        assertEquals(times, cluster.getLeaderFsm().getSaveSnapshotTimes());
+        assertEquals(snapshotTimes + 1, cluster.getLeaderFsm().getSaveSnapshotTimes());
     }
 
     @Test
@@ -2213,13 +2210,13 @@ public void testAutoSnapshot() throws Exception {
         // wait node elect self as leader
         Thread.sleep(2000);
 
-        this.sendTestTaskAndWait(node);
+        sendTestTaskAndWait(node);
 
-        assertEquals(-1, fsm.getSnapshotIndex());
-        assertEquals(0, fsm.getSaveSnapshotTimes());
         // wait for auto snapshot
         Thread.sleep(10000);
-        assertEquals(1, fsm.getSaveSnapshotTimes());
+        // first snapshot will be triggered randomly
+        final int times = fsm.getSaveSnapshotTimes();
+        assertTrue("snapshotTimes=" + times, times >= 1);
         assertTrue(fsm.getSnapshotIndex() > 0);
 
         final CountDownLatch latch = new CountDownLatch(1);
@@ -3250,8 +3247,9 @@ public void testChangePeersChaosApplyTasks() throws Exception {
         assertEquals(10, cluster.getFsms().size());
         try {
             for (final MockStateMachine fsm : cluster.getFsms()) {
-                assertTrue(fsm.getLogs().size() >= 5000 * threads);
-                assertTrue(fsm.getLogs().size() - 5000 * threads < 100);
+                final int logSize = fsm.getLogs().size();
+                assertTrue("logSize= " + logSize, logSize >= 5000 * threads);
+                assertTrue("logSize= " + logSize, logSize - 5000 * threads < 100);
             }
         } finally {
             cluster.stopAll();