tiflash: update scale doc for 4.0

reference/tiflash/scale.md

@@ -10,86 +10,40 @@ This document describes how to scale in and out nodes in the TiFlash cluster.
 
 ## Scale out a TiFlash node
 
-The following example shows how to scale out a TiFlash node if you deploy TiFlash on the `192.168.1.1` node.
+If you need to add a TiFlash node to the `172.19.0.104` host, take the following steps:
 
-1. Edit the `inventory.ini` file to add the TiFlash node information:
+1. Create the `scale-out.yaml` file to add the TiFlash node information:
 
     Currently, you can only add IP but not domain name.
 
     {{< copyable "" >}}
 
     ```ini
-    [tiflash_servers]
-    192.168.1.1
+    tiflash_servers:
+      - host: 172.19.0.104
     ```
 
-2. Edit the `hosts.ini` file to add the node information:
-
-    {{< copyable "" >}}
-
-    ```ini
-    [servers]
-    192.168.1.1
-    [all:vars]
-    username = tidb
-    ntp_server = pool.ntp.org
-    ```
-
-3. Initialize the new node:
-
-    - Configure the SSH mutual trust and sudo rules on the Control Machine:
-
-        {{< copyable "shell-regular" >}}
-
-        ```shell
-        ansible-playbook -i hosts.ini create_users.yml -l 192.168.1.1 -u root -k
-        ```
-
-    - Install the NTP service on the target machine:
-
-        {{< copyable "shell-regular" >}}
-
-        ```shell
-        ansible-playbook -i hosts.ini deploy_ntp.yml -u tidb -b
-        ```
-
-    - Initialize the node on the target machine:
-
-        {{< copyable "shell-regular" >}}
-
-        ```shell
-        ansible-playbook bootstrap.yml -l 192.168.1.1
-        ```
-
-4. Deploy the new node:
-
-    {{< copyable "shell-regular" >}}
-
-    ```shell
-    ansible-playbook deploy.yml -l 192.168.1.1
-    ```
-
-5. Start the new node:
+2. Run the scale-out command:
 
     {{< copyable "shell-regular" >}}
 
     ```shell
-    ansible-playbook start.yml -l 192.168.1.1
+    tiup cluster scale-out test scale-out.yaml
     ```
 
-6. Update the configuration of Prometheus and restart it:
+3. View the cluster status:
 
     {{< copyable "shell-regular" >}}
 
     ```shell
-    ansible-playbook rolling_update_monitor.yml --tags=prometheus
+    tiup cluster display test
     ```
 
-7. Access the monitoring platform using your browser, and view the status of the cluster and the new node.
+4. Access the monitoring platform using your browser, and view the status of the cluster and the new node.
 
 ## Scale in a TiFlash node
 
-The following example shows how to scale in a TiFlash node if you stop the TiFlash service on the `192.168.1.1` node.
+If you want to stop the TiFlash service on the `172.19.0.104` node, take the following steps:
 
 > **Note:**
 >
@@ -104,25 +58,15 @@ The following example shows how to scale in a TiFlash node if you stop the TiFla
     {{< copyable "shell-regular" >}}
 
     ```shell
-    ansible-playbook stop.yml -l 192.168.1.1
+    tiup cluster scale-in test --node 172.19.0.104:9000
     ```
 
-    If the node still has other services and you want to stop TiFlash only, use the following command:
-
-    {{< copyable "shell-regular" >}}
-
-    ```shell
-    ansible-playbook stop.yml -t tiflash -l 192.168.1.1
-    ```
-
-4. Edit the `inventory.ini` and `hosts.ini` files to remove the node information.
-
-5. Update the configuration of Prometheus and restart it:
+4. View the cluster status:
 
     {{< copyable "shell-regular" >}}
 
     ```shell
-    ansible-playbook rolling_update_monitor.yml --tags=prometheus
+    tiup cluster display test
     ```
 
-6. Access the monitoring platform using your browser, and view the status of the cluster.
+5. Access the monitoring platform using your browser, and view the status of the cluster.