Optimize quick start guide (#1232)

* Migrate figures to OSS

* Delete 1.what-is-br.md

* Update explorer-console.md

* Delete explorer-console.md

* Create explorer-console.md

* Update explorer-console.md

* optimize quick start

docs-2.0/2.quick-start/1.quick-start-workflow.md

@@ -18,6 +18,10 @@ Users can quickly deploy and use Nebula Graph in the following steps.
 
   Then users can use clients to connect to Nebula Graph. Nebula Graph supports a variety of clients. This topic will describe how to use Nebula Console to connect to Nebula Graph.
 
-4. [CRUD in Nebula Graph](4.nebula-graph-crud.md)
+4. [Register the Storage Service](3.1add-storage-hosts.md)
+
+  When connecting to Nebula Graph for the first time, users must register the Storage Service before querying data.
+
+5. [CRUD in Nebula Graph](4.nebula-graph-crud.md)
 
   Users can use nGQL (Nebula Graph Query Language) to run CRUD after connecting to Nebula Graph.

docs-2.0/2.quick-start/3.1add-storage-hosts.md

@@ -0,0 +1,49 @@
+# Register the Storage Service
+
+When connecting to Nebula Graph for the first time, you have to add the Storage hosts, and confirm that all the hosts are online.
+
+!!! compatibility
+
+    - Starting from Nebula Graph 3.0.0, you have to run `ADD HOSTS` before reading or writing data into the Storage Service.
+    - In earlier versions, `ADD HOSTS` is neither needed nor supported.
+
+## Prerequisites
+
+You have [connnected to Nebula Graph](3.connect-to-nebula-graph.md).
+
+## Steps
+
+1. Add the Storage hosts.
+
+  Run the following command to add hosts:
+
+  ```ngql
+  ADD HOSTS <ip>:<port> [,<ip>:<port> ...];
+  ```
+
+  <!--
+  ```ngql
+  ADD HOSTS <ip>:<port> [,<ip>:<port> ...] [INTO NEW ZONE "<new_zone_name>"];
+  ```
+  -->
+
+  Example：
+
+  ```ngql
+  nebula> ADD HOSTS 192.168.10.100:9779, 192.168.10.101:9779, 192.168.10.102:9779;
+  ```
+
+2. Check the status of the hosts to make sure that they are all online.
+
+  ```ngql
+  nebula> SHOW HOSTS;
+  +------------------+------+-----------+----------+--------------+----------------------  +------------------------+---------+
+  | Host             | Port | HTTP port | Status   | Leader count | Leader distribution  |   Partition distribution | Version |
+  +------------------+------+-----------+----------+--------------+----------------------  +------------------------+---------+
+  | "192.168.10.100" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No   valid partition"   | "3.1.0" |
+  | "192.168.10.101" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No   valid partition"   | "3.1.0" |
+  | "192.168.10.102" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No   valid partition"   | "3.1.0" |
+  +------------------+------+-----------+----------+--------------+----------------------  +------------------------+---------+
+  ```
+
+  The `Status` column of the result above shows that all Storage hosts are online.

docs-2.0/2.quick-start/4.nebula-graph-crud.md

@@ -25,51 +25,6 @@ In this topic, we will use the following dataset to demonstrate basic CRUD opera
 
 ![The demo dataset](https://docs-cdn.nebula-graph.com.cn/figures/dataset-for-crud.png)
 
-## Manage the Storage services in a Nebula Graph cluster
-
-First, add the Storage services to a Nebula Graph cluster. 
-
-<!--
-For more information, see [Manage zone](../4.deployment-and-installation/5.zone.md)。
--->
-
-!!! compatibility
-
-    From Nebula Graph version 3.0.0, the Storage services added in the configuration files **CANNOT** be read or written directly. The configuration files only register the Storage services into the Meta services. You must run the `ADD HOSTS` command to read and write data on Storage servers.
-
-```ngql
-ADD HOSTS <ip>:<port> [,<ip>:<port> ...];
-```
-
-<!--
-```ngql
-ADD HOSTS <ip>:<port> [,<ip>:<port> ...] [INTO NEW ZONE "<new_zone_name>"];
-```
--->
-
-Example：
-
-```ngql
-nebula> ADD HOSTS 192.168.10.100:9779, 192.168.10.101:9779, 192.168.10.102:9779;
-```
-
-## Check the machine status in the Nebula Graph cluster
-
-We recommend that you check the machine status to make sure that all the Storage services are connected to the Meta services. Run `SHOW HOSTS` as follows.
-
-```ngql
-nebula> SHOW HOSTS;
-+------------------+------+-----------+----------+--------------+----------------------+------------------------+---------+
-| Host             | Port | HTTP port | Status   | Leader count | Leader distribution  | Partition distribution | Version |
-+------------------+------+-----------+----------+--------------+----------------------+------------------------+---------+
-| "192.168.10.100" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No valid partition"   | "3.1.0" |
-| "192.168.10.101" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No valid partition"   | "3.1.0" |
-| "192.168.10.102" | 9779 | 19669     | "ONLINE" | 0            | "No valid partition" | "No valid partition"   | "3.1.0" |
-+------------------+------+-----------+----------+--------------+----------------------+------------------------+---------+
-```
-
-From the **Status** column of the table in the returned results, you can see that all the Storage services are online.
-
 ### Async implementation of `CREATE` and `ALTER`
 
 !!! caution

docs-2.0/backup-and-restore/nebula-br/1.what-is-br.md

@@ -98,7 +98,7 @@ To back up data, the BR sends a backup request to the leader metad process to tr
   
 This figure shows how the backup is implemented.
 
-![The figure shows the backup procedure](../../figs/ng-ug-001.png "Implementation of backup")
+![The figure shows the backup procedure](https://docs-cdn.nebula-graph.com.cn/figures/ng-ug-001.png "Implementation of backup")
 
 When backup files are generated, the file names are generated automatically. A folder name is in the format of `BACKUP_YY_MM_DD_HH_mm_SS`, of which,
 
@@ -137,7 +137,7 @@ The restoration process is implemented as follows:
 
 This figure shows how the restoration process is implemented.
 
-![The figure shows the restoration process](../../figs/ng-ug-002.png "Implementation of restoration")
+![The figure shows the restoration process](https://docs-cdn.nebula-graph.com.cn/figures/ng-ug-002.png "Implementation of restoration")
 -->
 
 

docs-2.0/nebula-explorer/explorer-console.md

@@ -4,4 +4,4 @@ Explorer console allows you to enter nGQL statements and visualize the query res
 
 At the upper right corner of the page, click ![console](figs/nav-console.png) to enter the console page.
 
-The Explorer's console feature is the same as Studio's. For more information, see [Console](../nebula-studio/quick-start/st-ug-console.md).
+The Explorer's console feature is the same as Studio's. For more information, see [Console](../nebula-studio/quick-start/st-ug-console.md).

docs-2.0/reuse/source_connect-to-nebula-graph.md

@@ -1,5 +1,9 @@
 This topic provides basic instruction on how to use the native CLI client Nebula Console to connect to Nebula Graph.
 
+!!! caution
+
+    When connecting to Nebula Graph for the first time, you must [register the Storage Service](../2.quick-start/3.1add-storage-hosts.md) before querying data.
+
 Nebula Graph supports multiple types of clients, including a CLI client, a GUI client, and clients developed in popular programming languages. For more information, see the [client list](../14.client/1.nebula-client.md).
 
 ## Prerequisites

mkdocs.yml

@@ -147,7 +147,8 @@ nav:
       - Step 1 Install Nebula Graph: 2.quick-start/2.install-nebula-graph.md
       - Step 2 Manage Nebula Graph Service: 2.quick-start/5.start-stop-service.md
       - Step 3 Connect to Nebula Graph: 2.quick-start/3.connect-to-nebula-graph.md
-      - Step 4 Use nGQL (CRUD): 2.quick-start/4.nebula-graph-crud.md
+      - Step 4 Register the Storage Service: 2.quick-start/3.1add-storage-hosts.md
+      - Step 5 Use nGQL (CRUD): 2.quick-start/4.nebula-graph-crud.md
       - nGQL cheatsheet: 2.quick-start/6.cheatsheet-for-ngql.md
 
   - nGQL guide: