What Are the Functions of the Default Security Group Rule?



An inbound security group rule enables external access to ECSs in a security group, and an outbound security group rule enables ECSs in a security group to access external networks.


If no access rule is configured for a security group after an ECS is added to the security group, communication between the ECS and the external network is blocked.


The default inbound rule enables an ECS to be accessed by other ECSs in the same security group, and the default outbound rule enables ECSs in the security group to access external networks.


Security groups cannot resolve the problems caused by network faults or incorrect network configuration. For example, when two ECSs cannot communicate with each other due to a network problem, a security group rule will also not allow them to communicate.



Scroll to top