Getting Started

(Optional) Modifying Security Group Rules

A security group is a collection of access control rules to control traffic to and from cloud resources, such as cloud servers, containers, and databases. Cloud resources associated with the same security group have the same security requirements and are mutually trusted within a VPC.

You can modify security group rules, for example, by adding, modifying, or deleting a TCP port, as follows:

• Add an inbound rule and configure a TCP port if needed.
• Inappropriate security group settings may cause serious security risks. You can modify security group rules to ensure the network security of your ECSs.
• If the source or destination IP address of an inbound or outbound security group rule changes, or a port needs to be disabled, you can delete the security group rule.

Viewing Your Resources and Testing Network Connectivity

1. Log in to the EIP console, create two EIPs, and bind them to the two ECSs created in Figure 9 respectively.
   Figure 1 Creating EIPs

   

2. Log in to the two ECSs created in Figure 9, deploy the httpd service on each ECS, and run the command below. Note that you can configure the message in the double quotation marks in the second line whatever you like. If the load balancer routes the request to the ECSs, this message will be returned.

   yum -y install httpd

   echo "www.test01.com" > /var/www/html/index.html

   chmod 777 /var/www/html/index.html

   systemctl start httpd

   curl localhost

   Figure 2 Logging in to the ECSs

   

   Figure 3 Installing the httpd service

   

   Figure 4 Installing the httpd service

   

3. Unbind the EIPs bound to the two ECSs in 2 and release the EIPs.
   Figure 5 Unbinding and releasing the EIPs

   

4. On the ELB console, view the dedicated load balancer you have created for deploying this solution.
   Figure 6 Viewing the load balancer

   

5. Enter the EIP address assigned in 4 in the address box of your browser to access the dedicated load balancer. If the following two pages are displayed, the load balancer routes the requests to the two ECSs.
   Figure 7 Verifying that the request is routed to one ECS

   

   Figure 8 Verifying that the request is routed to the other ECS