Fixed port in use issue occurs during testcase execution

go/test/endtoend/backup/backup_test.go

@@ -130,7 +130,7 @@ func TestMasterReplicaSameBackup(t *testing.T) {
 	verifyRestoreTablet(t, replica1, "SERVING")
 
 	// wait for replica1 to catch up.
-	cluster.VerifyRowsInTablet(t, replica2, keyspaceName, 3)
+	cluster.VerifyRowsInTablet(t, replica1, keyspaceName, 3)
 
 	// This is to test that replicationPosition is processed correctly
 	// while doing backup/restore after a reparent.
@@ -147,7 +147,7 @@ func TestMasterReplicaSameBackup(t *testing.T) {
 	// Force replica1 to restore from backup.
 	verifyRestoreTablet(t, replica1, "SERVING")
 
-	cluster.VerifyRowsInTablet(t, replica2, keyspaceName, 4)
+	cluster.VerifyRowsInTablet(t, replica1, keyspaceName, 4)
 	replica2.VttabletProcess.TearDown()
 	restartMasterReplica(t)
 }

go/test/endtoend/cluster/cluster_process.go

@@ -19,17 +19,22 @@ package cluster
 import (
 	"flag"
 	"fmt"
+	"io/ioutil"
 	"math/rand"
 	"os"
 	"os/exec"
 	"path"
+	"strconv"
 	"time"
 
 	"vitess.io/vitess/go/vt/log"
 )
 
 // DefaultCell : If no cell name is passed, then use following
-const DefaultCell = "zone1"
+const (
+	DefaultCell      = "zone1"
+	DefaultStartPort = 6700
+)
 
 var (
 	keepData = flag.Bool("keep-data", false, "don't delete the per-test VTDATAROOT subfolders")
@@ -498,12 +503,33 @@ func (cluster *LocalProcessCluster) StartVtworker(cell string, extraArgs ...stri
 // GetAndReservePort gives port for required process
 func (cluster *LocalProcessCluster) GetAndReservePort() int {
 	if cluster.nextPortForProcess == 0 {
-		cluster.nextPortForProcess = getRandomNumber(20000, 15000)
+		cluster.nextPortForProcess = getPort()
 	}
 	cluster.nextPortForProcess = cluster.nextPortForProcess + 1
 	return cluster.nextPortForProcess
 }
 
+// getPort checks if we have recent used port info in /tmp/todaytime.port
+// If no, then use a random port and save that port + 200 in the above file
+// If yes, then return that port, and save port + 200 in the same file
+// here, assumptions is 200 ports might be consumed for all tests in a package
+func getPort() int {
+	tmpPortFileName := path.Join(os.TempDir(), time.Now().Format("01022006.port"))
+	var port int
+	if _, err := os.Stat(tmpPortFileName); os.IsNotExist(err) {
+		port = getVtStartPort()
+	} else {
+		result, _ := ioutil.ReadFile(tmpPortFileName)
+		cport, err := strconv.Atoi(string(result))
+		if err != nil || cport > 60000 || cport == 0 {
+			cport = getVtStartPort()
+		}
+		port = cport
+	}
+	ioutil.WriteFile(tmpPortFileName, []byte(fmt.Sprintf("%d", port+200)), 0666)
+	return port
+}
+
 // GetAndReserveTabletUID gives tablet uid
 func (cluster *LocalProcessCluster) GetAndReserveTabletUID() int {
 	if cluster.BaseTabletUID == 0 {
@@ -517,6 +543,17 @@ func getRandomNumber(maxNumber int32, baseNumber int) int {
 	return int(rand.Int31n(maxNumber)) + baseNumber
 }
 
+func getVtStartPort() int {
+	osVtPort := os.Getenv("VTPORTSTART")
+	if osVtPort != "" {
+		cport, err := strconv.Atoi(string(osVtPort))
+		if err == nil {
+			return cport
+		}
+	}
+	return DefaultStartPort
+}
+
 // GetVttabletInstance creates a new vttablet object
 func (cluster *LocalProcessCluster) GetVttabletInstance(tabletType string, UID int, cell string) *Vttablet {
 	if UID == 0 {

test/config.json

@@ -451,6 +451,15 @@
 			"RetryMax": 0,
 			"Tags": []
 		},
+		"clustertest": {
+			"File": "clustertest.go",
+			"Args": ["vitess.io/vitess/go/test/endtoend/clustertest"],
+			"Command": [],
+			"Manual": false,
+			"Shard": 11,
+			"RetryMax": 0,
+			"Tags": []
+		},
 		"initial_sharding": {
 			"File": "initial_sharding.go",
 			"Args": ["vitess.io/vitess/go/test/endtoend/sharding/initialsharding/v3"],