diff --git a/framework/src/test/java/org/tron/common/backup/BackupManagerTest.java b/framework/src/test/java/org/tron/common/backup/BackupManagerTest.java
new file mode 100644
index 00000000000..8a5ff4f4bc2
--- /dev/null
+++ b/framework/src/test/java/org/tron/common/backup/BackupManagerTest.java
@@ -0,0 +1,90 @@
+package org.tron.common.backup;
+
+import java.lang.reflect.Field;
+import java.net.InetSocketAddress;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.ScheduledExecutorService;
+import org.junit.Assert;
+import org.junit.Test;
+import org.tron.common.backup.message.KeepAliveMessage;
+import org.tron.common.backup.socket.UdpEvent;
+import org.tron.common.parameter.CommonParameter;
+import org.tron.core.Constant;
+import org.tron.core.config.args.Args;
+
+public class BackupManagerTest {
+
+  @Test
+  public void test() throws Exception {
+    String[] a = new String[0];
+    Args.setParam(a, Constant.TESTNET_CONF);
+    CommonParameter parameter = CommonParameter.getInstance();
+    parameter.setBackupPriority(8);
+    List<String> members = new ArrayList<>();
+    members.add("127.0.0.2");
+    parameter.setBackupMembers(members);
+
+    BackupManager manager = new BackupManager();
+
+    Field field =  manager.getClass().getDeclaredField("localIp");
+    field.setAccessible(true);
+    field.set(manager, "127.0.0.1");
+
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.MASTER);
+
+    field =  manager.getClass().getDeclaredField("executorService");
+    field.setAccessible(true);
+    ScheduledExecutorService executorService = (ScheduledExecutorService) field.get(manager);
+    manager.init();
+    executorService.shutdown();
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.INIT);
+
+    /* ip not in the members */
+    manager.setStatus(BackupManager.BackupStatusEnum.INIT);
+    KeepAliveMessage message = new KeepAliveMessage(false, 6);
+    InetSocketAddress address = new InetSocketAddress("127.0.0.3", 1000);
+    UdpEvent event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.INIT);
+
+    /* ip not the member */
+    address = new InetSocketAddress("127.0.0.3", 1000);
+    message = new KeepAliveMessage(false, 6);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.INIT);
+
+    /* keepAliveMessage.getFlag() || peerPriority > priority */
+    address = new InetSocketAddress("127.0.0.2", 1000);
+    message = new KeepAliveMessage(false, 6);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.INIT);
+
+    /* keepAliveMessage.getFlag() || peerPriority > priority */
+    message = new KeepAliveMessage(false, 10);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.SLAVER);
+
+    /* keepAliveMessage.getFlag() || peerPriority > priority */
+    manager.setStatus(BackupManager.BackupStatusEnum.INIT);
+    message = new KeepAliveMessage(true, 6);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.SLAVER);
+
+    manager.setStatus(BackupManager.BackupStatusEnum.MASTER);
+    message = new KeepAliveMessage(false, 10);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.MASTER);
+
+    message = new KeepAliveMessage(true, 10);
+    event = new UdpEvent(message, address);
+    manager.handleEvent(event);
+    Assert.assertEquals(manager.getStatus(), BackupManager.BackupStatusEnum.SLAVER);
+
+  }
+}
diff --git a/framework/src/test/java/org/tron/common/backup/KeepAliveMessageTest.java b/framework/src/test/java/org/tron/common/backup/KeepAliveMessageTest.java
new file mode 100644
index 00000000000..a93e044db03
--- /dev/null
+++ b/framework/src/test/java/org/tron/common/backup/KeepAliveMessageTest.java
@@ -0,0 +1,32 @@
+package org.tron.common.backup;
+
+import static org.tron.common.backup.message.UdpMessageTypeEnum.BACKUP_KEEP_ALIVE;
+
+import org.junit.Test;
+import org.testng.Assert;
+import org.tron.common.backup.message.KeepAliveMessage;
+import org.tron.protos.Discover;
+
+public class KeepAliveMessageTest {
+
+  @Test
+  public void test() throws Exception {
+    KeepAliveMessage m1 = new KeepAliveMessage(true, 10);
+    Assert.assertTrue(m1.getFlag());
+    Assert.assertEquals(m1.getPriority(), 10);
+    Assert.assertEquals(m1.getType(), BACKUP_KEEP_ALIVE);
+    Assert.assertEquals(m1.getFrom(), null);
+    Assert.assertEquals(m1.getTimestamp(), 0);
+    Assert.assertEquals(m1.getData().length + 1, m1.getSendData().length);
+
+
+    Discover.BackupMessage backupMessage = Discover.BackupMessage.newBuilder()
+            .setFlag(true).setPriority(10).build();
+    KeepAliveMessage m2 = new KeepAliveMessage(backupMessage.toByteArray());
+    Assert.assertTrue(m2.getFlag());
+    Assert.assertEquals(m2.getPriority(), 10);
+    Assert.assertEquals(m2.getType(), BACKUP_KEEP_ALIVE);
+
+    Assert.assertEquals(m2.getMessageId().getBytes(), m1.getMessageId().getBytes());
+  }
+}
diff --git a/framework/src/test/java/org/tron/common/backup/UdpMessageTypeEnumTest.java b/framework/src/test/java/org/tron/common/backup/UdpMessageTypeEnumTest.java
new file mode 100644
index 00000000000..e3ded4a23e5
--- /dev/null
+++ b/framework/src/test/java/org/tron/common/backup/UdpMessageTypeEnumTest.java
@@ -0,0 +1,23 @@
+package org.tron.common.backup;
+
+import static org.tron.common.backup.message.UdpMessageTypeEnum.BACKUP_KEEP_ALIVE;
+import static org.tron.common.backup.message.UdpMessageTypeEnum.UNKNOWN;
+
+import org.junit.Test;
+import org.testng.Assert;
+import org.tron.common.backup.message.UdpMessageTypeEnum;
+
+public class UdpMessageTypeEnumTest {
+
+  @Test
+  public void test() {
+    UdpMessageTypeEnum type = UdpMessageTypeEnum.fromByte((byte) 5);
+    Assert.assertEquals(type.getType(), (byte) 0x05);
+    Assert.assertEquals(type, BACKUP_KEEP_ALIVE);
+
+
+    type = UdpMessageTypeEnum.fromByte((byte) 1);
+    Assert.assertEquals(type.getType(), (byte) 0xFF);
+    Assert.assertEquals(type, UNKNOWN);
+  }
+}