docs: update scale out docs (#2031)

* docs: update scale out docs

* update

* Update scale.md

Co-authored-by: LU MIAN <[email protected]>

Author: dl239

docs/en/maintain/scale.md

@@ -6,6 +6,15 @@ With the development of business, dynamic scale-out is required if the current c
 
 ### Step 1. Starting a new tablet node
 
+You need to first start a new tablet node as following steps, please refer to the [deploy doc](../deploy/install_deploy.md) for details:
+- Check time and zone settings, disable `THP` and `swap`
+- Download the package
+- Modify the configuration file: conf/tablet.flags
+- Start a new tablet
+  ```bash
+    sh bin/start.sh start tablet
+  ```
+
 After startup, you need to check whether the new node has joined the cluster. If the `showtablet` command is executed and the new node endpoint is listed, it means that it has joined the cluster
 
 ```bash

docs/zh/maintain/scale.md

@@ -5,7 +5,14 @@
 随着业务的发展, 当前集群的拓扑不能满足要求就需要动态的扩容。扩容就是把一部分分片从现有tablet节点迁移到新的tablet节点上从而减小内存占用
 
 ### 1 启动一个新的tablet节点
-
+按照如下步骤启动tablet节点，参考[部署文档](../deploy/install_deploy.md)
+- 检查时间和时区，关闭THP和swap
+- 下载部署包到新的节点并解压
+- 修改conf/tablet.flags配置文件，zk_cluster和zk_root_path和集群中其他节点保持一致。修改endpoint。
+- 启动tablet
+  ```bash
+    sh bin/start.sh start tablet
+  ```
 启动后查看新增节点是否加入集群。如果执行showtablet命令列出了新节点endpoint说明已经加入到集群中
 
 ```bash