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Virtual Private Cloud

Security group

Default Security Group

Default Security Group

The default security group acts as a fallback configuration, ensuring that every ENI is associated with a security group.

Action description

For convenience, the system automatically creates a default security group when a VPC is created:

The default security group comes with several commonly used rules pre-configured. For details, see the Default security group rule below.

The Default security group cannot be manually deleted; it is deleted only when its associated VPC is deleted.

Users can add, delete, and modify rules within the default security group.

Default security group rules

Details of the default rules for the default security group are as follows:

Inbound rule

Inbound	Priority	Strategy	Agreement	Port range	Source	Description
Inbound	100	Allow	ALL	ALL	This security group	Allow ECSs within the same security group to communicate with each other
Inbound	100	Allow	ICMP	ALL	0.0.0.0/0	Allows the use of the ping program to test the connectivity of ECSs
Inbound	100	Allow	ICMPV6	ALL	::/0	Allows the use of the ping program to test the connectivity of ECSs
Inbound	100	Allow	TCP	22	0.0.0.0/0	Allow SSH remote login to Linux servers
Inbound	100	Allow	TCP	80	0.0.0.0/0	Allow access to websites using the HTTP protocol
Inbound	100	Allow	TCP	443	0.0.0.0/0	Allow access to websites using the HTTPS protocol
Inbound	100	Allow	TCP	3389	0.0.0.0/0	Allows remote login to Windows ECS

Outbound rule

Outbound	Priority	Strategy	Agreement	Port range	Destination address	Description
Outbound	100	Allow	ALL	ALL	0.0.0.0/0	Allow all IPv4 traffic
Outbound	100	Allow	ALL	ALL	::/0	Allow all IPv6 traffic

Last updated: 2026.10.29 19:43:12