Connecting to a DB Instance from a Linux ECS

Operation Process

Step 1: Create an ECS

1. Log in to the management console and check whether there is an ECS available.
   • If there is a Linux ECS, go to 3.
   • If there is a Windows ECS, see Connecting to a DB Instance from a Windows ECS.
   • If no ECS is available, go to 2.
2. Create an ECS and select Linux (for example, CentOS) as its OS.

   To download a MySQL client to the ECS, bind an EIP to the ECS. The ECS must be in the same region, VPC, and security group as the RDS for MySQL DB instance for mutual communications.

   For details about how to purchase a Linux ECS, see "Purchasing an ECS" in Elastic Cloud Server User Guide.

3. On the ECS Information page, check the VPC of the ECS.

4. On the Basic Information page of the RDS for MySQL instance, check the VPC of the DB instance.

5. Ensure that the ECS and RDS for MySQL instance are in the same region and VPC. Then go to Step 2: Test Connectivity and Install a MySQL Client.
   • If they are not in the same region, create another ECS or DB instance. The ECS and DB instance in different regions cannot communicate with each other. To reduce network latency, deploy your DB instance in the region nearest to your workloads.
   • If the ECS and DB instance are in different VPCs, change the VPC of the ECS to that of the DB instance. For details, see "Changing a VPC" in the Elastic Cloud Server User Guide.

Step 2: Test Connectivity and Install a MySQL Client

1. Log in to the ECS. For details, see "Login Using VNC" in the Elastic Cloud Server User Guide.
2. On the Instances page of the RDS console, click the DB instance name.
3. Choose Connectivity & Security from the navigation pane. In the Connection Information area, obtain the floating IP address and database port of the DB instance.

4. On the ECS, check whether the floating IP address and database port of the DB instance can be connected.

   telnet 192.168.6.144 3306

   • If yes, network connectivity is normal.
   • If no, check the security group rules.
     • Check the outbound rules of the ECS security group. By default, all outgoing network traffic is allowed.

       If not all outgoing traffic is allowed, add an outbound rule for the floating IP address and port of the DB instance.

     • If in the security group of the DB instance, there is no inbound rule allowing the access from the private IP address and port of the ECS, add an inbound rule for the private IP address and port of the ECS. For details, see Configuring Security Group Rules.
5. Download the mysql client installation package for Linux to the ECS. The package mysql-community-client-8.0.28-1.el6.x86_64.rpm is used as an example.

   wget https://dev.mysql.com/get/mysql-community-client-8.0.28-1.el6.x86_64.rpm

   Note

   A MySQL client running a version later than that of the DB instance is recommended.

6. Install the MySQL client.

   rpm -ivh --nodeps mysql-community-client-8.0.28-1.el6.x86_64.rpm

   Note

   • If any conflicts occur during the installation, add the replacefiles parameter to the command and install the client again.

     rpm -ivh --replacefiles mysql-community-client-8.0.28-1.el6.x86_64.rpm

   • If a message is displayed prompting you to install a dependent package during the installation, add the nodeps parameter to the command and install the client again.

     rpm -ivh --nodeps mysql-community-client-8.0.28-1.el6.x86_64.rpm

Step 3: Connect to the DB Instance Using a CLI (Non-SSL Connection)

1. Run the following command on the ECS to connect to the DB instance:

   mysql -h <host> -P <port> -u <userName> -p

   Example:

   mysql -h 192.168.6.144 -P 3306 -u root -p

   Table 1 Parameter description

   Parameter	Description
   <host>	Floating IP address obtained in 3.
   <port>	Database port obtained in 3. The default value is 3306.
   <userName>	Administrator account root.

2. Enter the password of the database account if the following information is displayed:

   Enter password:
   
   

   Figure 1 Connection successful