Security groups that the system automatically creates for customers
Classic Network
The default network access control rules for default security groups under Classic networks are:
Intranet into direction deny all, out direction accept all;
Public network out of direction, into the direction are authorized 0.0.0.0/0 full pass, that is, the Internet accept all.
Proprietary Network VPC
The default network access control rules for the default security group under the Proprietary Network (VPC) are:
The internal network direction, direction are authorized 0.0.0.0/0 full pass, that is, allow and VPC any other instances of two-way visits.
The security group rules of proprietary network type, which do not distinguish between intranet and public network, set up the rules of entrance and exit direction of the net.
Security groups that you created yourself
Before adding a task security group rule, the intranet and public network default rules are all in the direction accept all, in the direction of deny all.