diff --git a/deployments/migrate-meta/README.md b/deployments/migrate-meta/README.md
index 895d816439..bef72b440c 100644
--- a/deployments/migrate-meta/README.md
+++ b/deployments/migrate-meta/README.md
@@ -6,22 +6,30 @@ Milvus 2.2 has changed the meta structure for segment index. To upgrade a Milvus
 
 
 > Note: 
-> 1. This script only applies to Milvus installed on a K8s cluster.
+> 1. This script only applies to Milvus installed on a K8s cluster which has storageclass.
+>    You can verify storageclass by running `kubectl get storageclass`. If you don't have a
+>    default storageclass, you need specify a storageclass via `-c <storage-class>` when running
+>    this script.
 > 2. This script only supports upgrading from Milvus v2.1.x to v2.2.0.
+> 3. If your milvus cluster use an external etcd service (which isn't installed with milvus), 
+>    you need specify etcd service explicitly via `-e <etcd-service-ip:etcd-service-port>` otherwise
+>    we use the default etcd service which installed with milvus.
 
 ## Parameters
 
-| Parameters   | Description                                                      | Default value                    | Required                |
-| ------------ | ---------------------------------------------------------------- | ---------------------------- | ----------------------- |
-| `i`          | The Milvus instance name.                                 | `None`                         | True                    |
-| `n`          | The namespace that Milvus is installed in.                | `default`                      | False                   |
-| `s`          | The source Milvus version.                                | `None`                         | True                    |
-| `t`          | The target Milvus version.                               | `None`                         | True                    |
-| `r`          | The root path of Milvus meta.                             | `by-dev`                       | False                   |
-| `w`          | The new Milvus image tag.                                 | `milvusdb/milvus:v2.2.0`       | False                   |
-| `m`          | The meta migration image tag.                             | `milvusdb/meta-migration:v2.2.0`       | False                   |
-| `o`          | The meta migration operation.                             | `migrate`                      | False                   |
-| `d`          | Whether to delete migration pod after the migration is completed.          | `false`                        | False                   |
+| Parameters   | Description                                               | Default value                    | Required                |
+| ------------ | ----------------------------------------------------------| -------------------------------- | ----------------------- |
+| `i`          | The Milvus instance name.                                 | `None`                           | True                    |
+| `n`          | The namespace that Milvus is installed in.                | `default`                        | False                   |
+| `s`          | The source Milvus version.                                | `None`                           | True                    |
+| `t`          | The target Milvus version.                                | `None`                           | True                    |
+| `r`          | The root path of Milvus meta.                             | `by-dev`                         | False                   |
+| `w`          | The new Milvus image tag.                                 | `milvusdb/milvus:v2.2.0`         | False                   |
+| `m`          | The meta migration image tag.                             | `milvusdb/meta-migration:v2.2.0` | False                   |
+| `o`          | The meta migration operation.                             | `migrate`                        | False                   |
+| `d`          | Whether to cleanup after migration is completed.          | `false`                          | False                   |
+| `c`          | The storage class for meta migration pvc.                 | `default storage class`          | False                   |
+| `e`          | The endpoints for etcd which used by milvus.              | `etcd svc installed with milvus` | False                   |
 > By default, the script only applies to migration from v2.1.x to v2.2.x. Rollback to the older version with the `rollback` operation first if an error occurs.
 
 
@@ -70,3 +78,15 @@ Milvus 2.2 has changed the meta structure for segment index. To upgrade a Milvus
 ./migrate.sh -i my-release -n milvus -s 2.1.1 -t 2.2.0 -r by-dev -o rollback -w <milvus-2-1-1-image>
 ./migrate.sh -i my-release -n milvus -s 2.1.1 -t 2.2.0 -r by-dev -o migrate -w <milvus-2-2-0-image>
 ```
+
+7. Specify the storage class explicitly.
+
+```shell
+./migrate.sh -i my-release -n milvus -s 2.1.4 -t 2.2.0 -c <special-storage-class>
+```
+
+8. Specify external etcd service.
+
+```shell
+./migrate.sh -i my-release -n milvus -s 2.1.4 -t 2.2.0 -e <etcd-svc-ip:etcd-svc-port>
+```
diff --git a/deployments/migrate-meta/migrate.sh b/deployments/migrate-meta/migrate.sh
index 93e4bb58df..9cf6734371 100755
--- a/deployments/migrate-meta/migrate.sh
+++ b/deployments/migrate-meta/migrate.sh
@@ -6,6 +6,9 @@ operation="migrate"
 image_tag="milvusdb/milvus:v2.2.0"
 meta_migration_pod_tag="milvusdb/meta-migration:v2.2.0"
 remove_migrate_pod_after_migrate="false"
+storage_class=""
+external_etcd_svc=""
+etcd_svc=""
 
 #-n namespace: The namespace that Milvus is installed in.
 #-i milvus_instance: The name of milvus instance.
@@ -14,8 +17,11 @@ remove_migrate_pod_after_migrate="false"
 #-r root_path: The milvus meta root path.
 #-w image_tag: The new milvus image tag.
 #-o operation: The operation: migrate/rollback.
+#-m meta_migration_pod_tag: The image for meta migration pod.
 #-d remove_migrate_pod_after_migrate: Remove migration pod after successful migration.
-while getopts "n:i:s:t:r:w:o:d:m:" opt_name
+#-c storage_class: The storage class for meta migration pvc.
+#-e external_etcd_svc: The endpoints for etcd which used by milvus.
+while getopts "n:i:s:t:r:w:o:m:c:e:d:" opt_name
 do
   case $opt_name in
     n) namespace=$OPTARG;;
@@ -27,6 +33,8 @@ do
     o) operation=$OPTARG;;
     m) meta_migration_pod_tag=$OPTARG;;
     d) remove_migrate_pod_after_migrate="true";;
+    c) storage_class=$OPTARG;;
+    e) external_etcd_svc=$OPTARG;;
     *) echo "Unkonwen parameters";;
   esac
 done
@@ -51,6 +59,72 @@ if [ ! $image_tag ]; then
   exit 1
 fi
 
+deployments=$(kubectl get deploy -n $namespace -l app.kubernetes.io/instance=$instance_name,app.kubernetes.io/name=milvus --output=jsonpath={.items..metadata.name})
+deploys=()
+replicas=()
+for d in $deployments; do
+  component=$(kubectl get deploy $d -n $namespace --output=jsonpath={.metadata.labels.component})
+  replica=$(kubectl get deploy $d -n $namespace --output=jsonpath={.spec.replicas})
+  if [ "$component" = "attu" ]; then
+    continue
+  fi
+  deploys+=("$d")
+done
+
+if [ ${#deploys[@]} -eq 0 ]; then
+  echo "There is no Milvus instance $instance_name in the namespace $namespace"
+  exit 1
+fi
+
+if [ ! $external_etcd_svc ]; then
+  svc=$(kubectl get svc -n $namespace -l app.kubernetes.io/instance=$instance_name,app.kubernetes.io/name=etcd -o name | grep -v headless | cut -d '/' -f 2)
+
+  if [ ! $svc ]; then
+    echo "Missing etcd service, please add it. For example:'./migrate.sh -e <etcd-svc-ip>:<etcd-svc-port>'"
+    exit 1
+  else
+    port=$(kubectl get svc -n $namespace $svc --output=jsonpath='{.spec.ports[?(@.name == "client")].port}')
+    if [ ! $port ]; then
+      echo "Missing etcd service port..."
+      exit 1
+    fi
+    etcd_svc="$svc:$port"
+  fi
+else
+  etcd_svc="$external_etcd_svc"
+fi
+
+scs=$(kubectl get storageclass --output=jsonpath='{.items..metadata.name}')
+if [ ! $storage_class ]; then
+  # check whether there a default storageclass
+  exists=0
+  for sc in $scs; do
+    default=$(kubectl get storageclass $sc --output=jsonpath='{.metadata.annotations.storageclass\.kubernetes\.io/is-default-class}')
+    if [ "$default" = "true" ] ; then
+      exists=1
+      break
+    fi
+  done
+
+  if [ $exists -eq 0 ] ; then
+    echo "No default storageclass, please specify a storageclass via -c <storage-class-name>"
+    exit 1
+  fi
+else
+  exists=0
+  for sc in $scs; do
+    if [ "$sc" = "$storage_class" ] ; then
+      exists=1
+      break
+    fi
+  done
+
+  if [ $exists -eq 0 ]; then
+    echo "Nonexistent storageclass, please make sure specified storageclass exists..."
+    exit 1
+  fi
+fi
+
 echo "Migration milvus meta will take four steps:"
 echo "1. Stop the milvus components"
 echo "2. Backup the milvus meta"
@@ -59,19 +133,34 @@ echo "4. Startup milvus components in new image version"
 echo
 
 
-replicas=()
-function fetch_deploy_replica(){
-  for deploy in $1;
-  do
-    replica=$(kubectl get deploy $deploy -n $namespace --output=jsonpath={.spec.replicas})
-    replicas+=("$deploy:$replica")
-  done
+function store_deploy_replicas(){
+  # store deploy replicas in a configmap
+  # first check whether config exists
+  data=$(kubectl get configmap "milvus-deploy-replicas-$instance_name" -n $namespace --output=jsonpath={.data.replicas} 2>/dev/null)
+  if [ ! "$data" ]; then
+    for d in ${deploys[@]}; do
+      replica=$(kubectl get deploy $d -n $namespace --output=jsonpath={.spec.replicas})
+      replicas+=("$d:$replica")
+    done
+    cat <<EOF | kubectl apply -n $namespace -f -
+    apiVersion: v1
+    kind: ConfigMap
+    metadata:
+      name: milvus-deploy-replicas-${instance_name}
+    data:
+      replicas: "${replicas[@]}"
+EOF
+  else
+    for d in $data; do
+      replicas+=("$d")
+    done
+  fi
 }
 
 function stop_milvus_deploy(){
-  echo "Stop milvus deployments: $1"
-  kubectl scale deploy -n $namespace $1 --replicas=0 > /dev/null
-  wait_for_milvus_stopped $1
+  echo "Stop milvus deployments: ${deploys[@]}"
+  kubectl scale deploy -n $namespace "${deploys[@]}" --replicas=0 > /dev/null
+  wait_for_milvus_stopped "${deploys[@]}"
   echo "Stopped..."
 }
 
@@ -172,20 +261,25 @@ function wait_for_rollback_done(){
     esac
   done
 }
+
 function generate_migrate_meta_cm_and_pvc(){
-  etcd_svc=$(kubectl get svc -n $namespace -l app.kubernetes.io/instance=$instance_name,app.kubernetes.io/name=etcd -o name | grep -v headless | cut -d '/' -f 2)
-  cat <<EOF | kubectl apply -n $namespace -f -
-  apiVersion: v1
-  kind: PersistentVolumeClaim
-  metadata:
-    name: milvus-meta-migration-backup-${instance_name}
-  spec:
-    accessModes:
-    - ReadWriteOnce
-    resources:
-      requests:
-        storage: 10Gi
+  # check whether pvc exists
+  exists=$(kubectl get pvc "milvus-meta-migration-backup-${instance_name}" -n $namespace --output=jsonpath={.metadata.name} 2>/dev/null)
+  if [ ! $exists ]; then
+    cat <<EOF | kubectl apply -n $namespace -f -
+    apiVersion: v1
+    kind: PersistentVolumeClaim
+    metadata:
+      name: milvus-meta-migration-backup-${instance_name}
+    spec:
+      accessModes:
+      - ReadWriteOnce
+      storageClassName: $storage_class
+      resources:
+        requests:
+          storage: 10Gi
 EOF
+  fi
   cat <<EOF | kubectl apply -n $namespace -f -
   apiVersion: v1
   kind: ConfigMap
@@ -206,7 +300,7 @@ EOF
 
       etcd:
         endpoints:
-          - $etcd_svc:2379
+          - $etcd_svc
         rootPath: $root_path
         metaSubPath: meta
         kvSubPath: kv
@@ -224,7 +318,7 @@ EOF
 
       etcd:
         endpoints:
-          - $etcd_svc:2379
+          - $etcd_svc
         rootPath: $root_path
         metaSubPath: meta
         kvSubPath: kv
@@ -242,7 +336,7 @@ EOF
 
       etcd:
         endpoints:
-          - $etcd_svc:2379
+          - $etcd_svc
         rootPath: $root_path
         metaSubPath: meta
         kvSubPath: kv
@@ -254,7 +348,7 @@ function backup_meta(){
   echo "Checking whether backup exists..."
   configmap_name="milvus-meta-migration-config-${instance_name}"
   backup_exists=$(kubectl get configmap $configmap_name -n $namespace --output=jsonpath={.metadata.annotations.backup})
-  if [ "$backup_exists" == "succeed" ]; then
+  if [ "$backup_exists" = "succeed" ]; then
     echo "Found previous backups, skip meta backup..."
   else
     cat <<EOF | kubectl apply -n $namespace -f -
@@ -292,7 +386,7 @@ function rollback_meta(){
   generate_migrate_meta_cm_and_pvc
   echo "Checking whether backup exists..."
   backup_exists=$(kubectl get configmap milvus-meta-migration-config -n $namespace --output=jsonpath={.metadata.annotations.backup})
-  if [ "$backup_exists" == "succeed" ]; then
+  if [ "$backup_exists" = "succeed" ]; then
     echo "Found previous backups, start meta rollback..."
   cat <<EOF | kubectl apply -n $namespace -f -
   apiVersion: v1
@@ -365,23 +459,16 @@ EOF
 
 function start_milvus_deploy(){
   echo "Starting milvus components..."
-  for deploy in "${replicas[@]}"
+  for d in "${replicas[@]}"
   do
     IFS=':'
-    read -a item <<< "$deploy"
+    read -a item <<< "$d"
     deploy_name="${item[0]}"
     replica_count="${item[1]}"
     echo "Starting $deploy_name..."
     component=$(kubectl get deploy -n $namespace $deploy_name --output=jsonpath={.metadata.labels.component})
-    kubectl patch deployment/$deploy_name -n $namespace --patch-file=/dev/stdin <<-EOF
-    spec:
-      replicas: $replica_count
-      template:
-        spec:
-          containers:
-          - name: $component
-            image: $image_tag
-EOF
+    kubectl patch deployment $deploy_name -n $namespace -p "{\"spec\":{\"template\": {\"spec\": {\"containers\":[{\"name\": \"$component\", \"image\": \"$image_tag\"}]}}}}"
+    kubectl scale deployment $deploy_name -n $namespace --replicas="$replica_count"
   done
 }
 
@@ -397,51 +484,47 @@ function wait_for_milvus_ready(){
       deploy_name="${item[0]}"
       replica_count="${item[1]}"
       count=$(kubectl get deploy $deploy_name -n $namespace --output=jsonpath={.status.readyReplicas})
-      if [ "$count" == "$replica_count" ] ; then
+      if [ "$count" = "$replica_count" ] ; then
         ready_count=`expr $ready_count + 1` 
       fi
     done
-    if [ "$total_component_count" == "$ready_count" ]; then
+    if [ "$total_component_count" = "$ready_count" ]; then
       break
     fi
     sleep 5
   done
 }
 
-deployments=$(kubectl get deploy -n $namespace -l app.kubernetes.io/instance=$instance_name,app.kubernetes.io/name=milvus --output=jsonpath={.items..metadata.name})
-if [ ${#deployments} == 0 ]; then
-	echo "There is no Milvus instance $instance_name in the namespace $namespace"
-else
-	 fetch_deploy_replica "${deployments[*]}"
-   stop_milvus_deploy "$deployments"
-   echo 
-   case $operation in
-     migrate)
-       echo "Starting to migrate milvus meta..."
-       migrate_meta
-       start_milvus_deploy
-       echo
-       echo "Upgrading is done. Waiting for milvus components to be ready again..."
-       wait_for_milvus_ready
-       if [ "$remove_migrate_pod_after_migrate" == "true" ]; then
-         kubectl delete pods -n $namespace "milvus-meta-migration-backup-${instance_name}" "milvus-meta-migration-${instance_name}"
-         kubectl delete pvc -n $namespace "milvus-meta-migration-backup-${instance_name}"
-         kubectl delete configmap -n $namespace "milvus-meta-migration-config-${instance_name}"
-       fi
-       echo "All milvus components are running. Enjoy your vector search..."
-       ;;
-     rollback)
-       echo "Starting to rollback milvus meta..."
-       rollback_meta
-       start_milvus_deploy
-       echo
-       echo "Rollbacking is done. Waiting for milvus components to be ready again..."
-       wait_for_milvus_ready
-       echo "All milvus components are running. Enjoy your vector search..."
-       ;;
-     *)
-       echo "Invalid operation..."
-       exit 6
-       ;;
-   esac
-fi
+store_deploy_replicas
+stop_milvus_deploy
+echo
+case $operation in
+ migrate)
+   echo "Starting to migrate milvus meta..."
+   migrate_meta
+   start_milvus_deploy
+   echo
+   echo "Upgrading is done. Waiting for milvus components to be ready again..."
+   wait_for_milvus_ready
+   if [ "$remove_migrate_pod_after_migrate" = "true" ]; then
+     kubectl delete pods -n $namespace "milvus-meta-migration-backup-${instance_name}" "milvus-meta-migration-${instance_name}"
+     kubectl delete pvc -n $namespace "milvus-meta-migration-backup-${instance_name}"
+     kubectl delete configmap -n $namespace "milvus-meta-migration-config-${instance_name}" "milvus-deploy-replicas-${instance_name}"
+     echo
+   fi
+   echo "All milvus components are running. Enjoy your vector search..."
+   ;;
+ rollback)
+   echo "Starting to rollback milvus meta..."
+   rollback_meta
+   start_milvus_deploy
+   echo
+   echo "Rollbacking is done. Waiting for milvus components to be ready again..."
+   wait_for_milvus_ready
+   echo "All milvus components are running. Enjoy your vector search..."
+   ;;
+ *)
+   echo "Invalid operation..."
+   exit 6
+   ;;
+esac