diff --git a/pkg/compute/tasks/instance_backup_delete_task.go b/pkg/compute/tasks/instance_backup_delete_task.go
index ad7ccc513e..a24081dc9c 100644
--- a/pkg/compute/tasks/instance_backup_delete_task.go
+++ b/pkg/compute/tasks/instance_backup_delete_task.go
@@ -61,13 +61,13 @@ func (self *InstanceBackupDeleteTask) OnKvmDiskBackupDelete(
 	backupId, _ := self.Params.GetString("del_backup_id")
 	// detach backup and instance
 	isjp := new(models.SInstanceBackupJoint)
+	isjp.SetModelManager(models.InstanceBackupJointManager, isjp)
 	err := models.InstanceBackupJointManager.Query().
 		Equals("instance_backup_id", isp.Id).Equals("disk_backup_id", backupId).First(isjp)
 	if err != nil {
 		self.taskFailed(ctx, isp, jsonutils.NewString(err.Error()))
 		return
 	}
-	isjp.SetModelManager(models.InstanceBackupJointManager, isjp)
 	err = isjp.Delete(ctx, self.UserCred)
 	if err != nil {
 		self.taskFailed(ctx, isp, jsonutils.NewString(err.Error()))
diff --git a/pkg/hostman/guestman/guesttasks.go b/pkg/hostman/guestman/guesttasks.go
index e5a5f2b4d9..4fb224dbe3 100644
--- a/pkg/hostman/guestman/guesttasks.go
+++ b/pkg/hostman/guestman/guesttasks.go
@@ -772,7 +772,7 @@ func (s *SGuestLiveMigrateTask) doMigrate() {
 }
 
 func (s *SGuestLiveMigrateTask) onSetMigrateDowntime(res string) {
-	s.Monitor.MigrateSetDowntime(options.HostOptions.DefaultLiveMigrateDowntime, s.startMigrateStatusCheck)
+	s.Monitor.MigrateSetParameter("downtime-limit", int(options.HostOptions.DefaultLiveMigrateDowntime*1000), s.startMigrateStatusCheck)
 }
 
 func (s *SGuestLiveMigrateTask) startMigrateStatusCheck(res string) {
diff --git a/pkg/hostman/hostinfo/hostpinger.go b/pkg/hostman/hostinfo/hostpinger.go
index 81d5ad767d..298205e34a 100644
--- a/pkg/hostman/hostinfo/hostpinger.go
+++ b/pkg/hostman/hostinfo/hostpinger.go
@@ -62,6 +62,7 @@ func NewHostPingTask(interval int) *SHostPingTask {
 }
 
 func (p *SHostPingTask) Start() {
+	log.Infof("Start host pinger ...")
 	var (
 		div    = 1
 		hostId = Instance().GetHostId()
@@ -83,6 +84,7 @@ func (p *SHostPingTask) Start() {
 }
 
 func (p *SHostPingTask) ping(div int, hostId string) error {
+	log.Debugf("ping region at %d...", div)
 	res, err := modules.Hosts.PerformAction(hostutils.GetComputeSession(context.Background()),
 		hostId, "ping", nil)
 	if err != nil {
diff --git a/pkg/hostman/monitor/hmp.go b/pkg/hostman/monitor/hmp.go
index da79242b15..96a03a9402 100644
--- a/pkg/hostman/monitor/hmp.go
+++ b/pkg/hostman/monitor/hmp.go
@@ -312,7 +312,7 @@ func (m *HmpMonitor) MigrateSetCapability(capability, state string, callback Str
 	m.Query(fmt.Sprintf("migrate_set_capability %s %s", capability, state), callback)
 }
 
-func (m *HmpMonitor) MigrateSetParameter(key string, val string, callback StringCallback) {
+func (m *HmpMonitor) MigrateSetParameter(key string, val interface{}, callback StringCallback) {
 	cmd := fmt.Sprintf("migrate_set_parameter %s %s", key, val)
 	m.Query(cmd, callback)
 }
diff --git a/pkg/hostman/monitor/monitor.go b/pkg/hostman/monitor/monitor.go
index 9c286ff81f..db53574721 100644
--- a/pkg/hostman/monitor/monitor.go
+++ b/pkg/hostman/monitor/monitor.go
@@ -177,7 +177,7 @@ type Monitor interface {
 
 	MigrateSetDowntime(dtSec float32, callback StringCallback)
 	MigrateSetCapability(capability, state string, callback StringCallback)
-	MigrateSetParameter(key, val string, callback StringCallback)
+	MigrateSetParameter(key string, val interface{}, callback StringCallback)
 	MigrateIncoming(address string, callback StringCallback)
 	Migrate(destStr string, copyIncremental, copyFull bool, callback StringCallback)
 	GetMigrateStatus(callback StringCallback)
diff --git a/pkg/hostman/monitor/qmp.go b/pkg/hostman/monitor/qmp.go
index 6641537742..161b0bb402 100644
--- a/pkg/hostman/monitor/qmp.go
+++ b/pkg/hostman/monitor/qmp.go
@@ -623,7 +623,7 @@ func (m *QmpMonitor) MigrateSetCapability(capability, state string, callback Str
 	m.Query(cmd, cb)
 }
 
-func (m *QmpMonitor) MigrateSetParameter(key string, val string, callback StringCallback) {
+func (m *QmpMonitor) MigrateSetParameter(key string, val interface{}, callback StringCallback) {
 	var (
 		cb = func(res *Response) {
 			callback(m.actionResult(res))