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How Do I Configure a Security Group?

The following describes how to configure security groups for intra-VPC access and public access.

Intra-VPC Access to DCS Instances

An ECS can communicate with a DCS instance if they belong to the same VPC and same subnet and security group rules are configured correctly.

  • If the ECS and DCS instance are configured with the same security group, network access in the group is not restricted by default.
  • If the ECS and DCS instance are configured with different security groups, add security group rules to ensure that the ECS and DCS instance can access each other.
    • Suppose that the ECS on which the client runs belongs to security group sg-ECS, and the DCS instance that the client will access belongs to security group sg-DCS.
    • Suppose that the port number of the DCS service is 6379.
    • The remote end is a security group or an IP address.
    1. Configuring security group for the ECS.

      Add the following outbound rule to allow the ECS to access the DCS instance.

    2. Configuring security group for the DCS instance.

      To ensure that your client can access the DCS instance, add the following inbound rule to the security group configured for the DCS instance:

      For the source IP address, use the specified IP address of the DCS instance. Avoid using 0.0.0.0/0 to prevent ECSs bound with the same security group from being attacked by Redis vulnerability exploits.

Public Access to DCS Instances

A client can access a DCS instance only after rules are correctly configured for the security group of the instance.

For example, for security group sg-DCS, you need to configure the following rules in the inbound direction:

Protocol: TCP; source IP address: 0.0.0.0/0 or a specified client address. When SSL is enabled, set the port number to 36379. When SSL is disabled, set the port number to 6379.

Figure 1 Security group rule (port 36379)
Figure 2 Security group rule (port 6379)