diff --git a/src/test/java/org/tikv/common/MockThreeStoresTest.java b/src/test/java/org/tikv/common/MockThreeStoresTest.java
index fa4dbe41e3..43063be7d1 100644
--- a/src/test/java/org/tikv/common/MockThreeStoresTest.java
+++ b/src/test/java/org/tikv/common/MockThreeStoresTest.java
@@ -42,9 +42,11 @@ public class MockThreeStoresTest extends PDMockServerTest {
   public void setup() throws IOException {
     super.setup();
 
-    int basePort;
-    try (ServerSocket s = new ServerSocket(0)) {
-      basePort = s.getLocalPort();
+    int[] ports = new int[3];
+    for (int i = 0; i < ports.length; i++) {
+      try (ServerSocket s = new ServerSocket(0)) {
+        ports[i] = s.getLocalPort();
+      }
     }
 
     ImmutableList<Metapb.Peer> peers =
@@ -65,17 +67,17 @@ public class MockThreeStoresTest extends PDMockServerTest {
     stores =
         ImmutableList.of(
             Metapb.Store.newBuilder()
-                .setAddress("127.0.0.1:" + basePort)
+                .setAddress("127.0.0.1:" + ports[0])
                 .setVersion("5.0.0")
                 .setId(0x1)
                 .build(),
             Metapb.Store.newBuilder()
-                .setAddress("127.0.0.1:" + (basePort + 1))
+                .setAddress("127.0.0.1:" + ports[1])
                 .setVersion("5.0.0")
                 .setId(0x2)
                 .build(),
             Metapb.Store.newBuilder()
-                .setAddress("127.0.0.1:" + (basePort + 2))
+                .setAddress("127.0.0.1:" + ports[2])
                 .setVersion("5.0.0")
                 .setId(0x3)
                 .build());
@@ -101,9 +103,9 @@ public class MockThreeStoresTest extends PDMockServerTest {
             region.getPeers(0),
             region.getPeersList(),
             stores.stream().map(TiStore::new).collect(Collectors.toList()));
-    for (int i = 0; i < 3; i++) {
+    for (int port : ports) {
       KVMockServer server = new KVMockServer();
-      server.start(this.region, basePort + i);
+      server.start(this.region, port);
       servers.add(server);
     }
   }
diff --git a/src/test/java/org/tikv/common/PDClientMockTest.java b/src/test/java/org/tikv/common/PDClientMockTest.java
index 3ba0e37439..10e0901d34 100644
--- a/src/test/java/org/tikv/common/PDClientMockTest.java
+++ b/src/test/java/org/tikv/common/PDClientMockTest.java
@@ -47,7 +47,8 @@ public class PDClientMockTest extends PDMockServerTest {
   @Test
   public void testCreate() throws Exception {
     try (PDClient client = session.getPDClient()) {
-      assertEquals(LOCAL_ADDR + ":" + leader.port, client.getPdClientWrapper().getLeaderInfo());
+      assertEquals(
+          LOCAL_ADDR + ":" + leader.getPort(), client.getPdClientWrapper().getLeaderInfo());
       assertEquals(CLUSTER_ID, client.getHeader().getClusterId());
     }
   }
@@ -55,17 +56,19 @@ public class PDClientMockTest extends PDMockServerTest {
   @Test
   public void testSwitchLeader() throws Exception {
     try (PDClient client = session.getPDClient()) {
-      client.trySwitchLeader(HTTP + LOCAL_ADDR + ":" + (leader.port + 1));
+      // Switch leader to server 1
+      client.trySwitchLeader(HTTP + LOCAL_ADDR + ":" + pdServers.get(1).getPort());
       assertEquals(
-          client.getPdClientWrapper().getLeaderInfo(), HTTP + LOCAL_ADDR + ":" + (leader.port + 1));
+          client.getPdClientWrapper().getLeaderInfo(),
+          HTTP + LOCAL_ADDR + ":" + pdServers.get(1).getPort());
     }
     tearDown();
     setup(LOCAL_ADDR_IPV6);
     try (PDClient client = session.getPDClient()) {
-      client.trySwitchLeader(HTTP + LOCAL_ADDR_IPV6 + ":" + (leader.port + 2));
+      client.trySwitchLeader(HTTP + LOCAL_ADDR_IPV6 + ":" + pdServers.get(2).getPort());
       assertEquals(
           client.getPdClientWrapper().getLeaderInfo(),
-          HTTP + LOCAL_ADDR_IPV6 + ":" + (leader.port + 2));
+          HTTP + LOCAL_ADDR_IPV6 + ":" + pdServers.get(2).getPort());
     }
   }
 
diff --git a/src/test/java/org/tikv/common/PDMockServer.java b/src/test/java/org/tikv/common/PDMockServer.java
index 3d64624f44..96c4970af9 100644
--- a/src/test/java/org/tikv/common/PDMockServer.java
+++ b/src/test/java/org/tikv/common/PDMockServer.java
@@ -37,8 +37,7 @@ import org.tikv.kvproto.Pdpb.TsoRequest;
 import org.tikv.kvproto.Pdpb.TsoResponse;
 
 public class PDMockServer extends PDGrpc.PDImplBase {
-
-  public int port;
+  private int port;
   private long clusterId;
   private Server server;
 
@@ -148,4 +147,8 @@ public class PDMockServer extends PDGrpc.PDImplBase {
   public long getClusterId() {
     return clusterId;
   }
+
+  public long getPort() {
+    return port;
+  }
 }
diff --git a/src/test/java/org/tikv/common/PDMockServerTest.java b/src/test/java/org/tikv/common/PDMockServerTest.java
index 1fd84f5ddb..e61a10cce9 100644
--- a/src/test/java/org/tikv/common/PDMockServerTest.java
+++ b/src/test/java/org/tikv/common/PDMockServerTest.java
@@ -38,28 +38,30 @@ public abstract class PDMockServerTest {
   }
 
   void setup(String addr) throws IOException {
-    int basePort;
-    try (ServerSocket s = new ServerSocket(0)) {
-      basePort = s.getLocalPort();
+    int[] ports = new int[3];
+    for (int i = 0; i < ports.length; i++) {
+      try (ServerSocket s = new ServerSocket(0)) {
+        ports[i] = s.getLocalPort();
+      }
     }
 
-    for (int i = 0; i < 3; i++) {
+    for (int i = 0; i < ports.length; i++) {
       PDMockServer server = new PDMockServer();
-      server.start(CLUSTER_ID, basePort + i);
+      server.start(CLUSTER_ID, ports[i]);
       server.addGetMembersListener(
           (request) ->
               GrpcUtils.makeGetMembersResponse(
                   server.getClusterId(),
-                  GrpcUtils.makeMember(1, "http://" + addr + ":" + basePort),
-                  GrpcUtils.makeMember(2, "http://" + addr + ":" + (basePort + 1)),
-                  GrpcUtils.makeMember(3, "http://" + addr + ":" + (basePort + 2))));
+                  GrpcUtils.makeMember(1, "http://" + addr + ":" + ports[0]),
+                  GrpcUtils.makeMember(2, "http://" + addr + ":" + ports[1]),
+                  GrpcUtils.makeMember(3, "http://" + addr + ":" + ports[2])));
       pdServers.add(server);
       if (i == 0) {
         leader = server;
       }
     }
 
-    TiConfiguration conf = TiConfiguration.createDefault(addr + ":" + leader.port);
+    TiConfiguration conf = TiConfiguration.createDefault(addr + ":" + ports[0]);
     conf.setKvMode("RAW");
     conf.setWarmUpEnable(false);
     conf.setTimeout(2000);
diff --git a/src/test/java/org/tikv/common/SeekLeaderStoreTest.java b/src/test/java/org/tikv/common/SeekLeaderStoreTest.java
index 201f10986f..891e676ee9 100644
--- a/src/test/java/org/tikv/common/SeekLeaderStoreTest.java
+++ b/src/test/java/org/tikv/common/SeekLeaderStoreTest.java
@@ -28,7 +28,6 @@ import org.tikv.kvproto.Pdpb;
 import org.tikv.raw.RawKVClient;
 
 public class SeekLeaderStoreTest extends MockThreeStoresTest {
-
   private RawKVClient createClient() {
     return session.createRawClient();
   }
diff --git a/src/test/java/org/tikv/common/SeekProxyStoreTest.java b/src/test/java/org/tikv/common/SeekProxyStoreTest.java
index e4b34c4fa3..6149a591cc 100644
--- a/src/test/java/org/tikv/common/SeekProxyStoreTest.java
+++ b/src/test/java/org/tikv/common/SeekProxyStoreTest.java
@@ -24,7 +24,6 @@ import org.tikv.common.KVMockServer.State;
 import org.tikv.raw.RawKVClient;
 
 public class SeekProxyStoreTest extends MockThreeStoresTest {
-
   private RawKVClient createClient() {
     return session.createRawClient();
   }