OpenStack Cloud Computing Cookbook - Fourth Edition

Managing security groups

In OpenStack, a security group describes a grouping of ports of similar security requirements. Security group rules are associated with security groups, and provide ingress and egress filtering capabilities to the group. Security group rules can reference other groups or remote networks using CIDR notation. The actual filtering takes place on the compute node at the "port" level, and may be implemented using iptables or as openflow rules depending on the firewall driver that is configured on a given node. Newly created projects each contain a security group named default that allows egress, or outbound, communication only. Ingress, or inbound, communication is denied.

Creating security groups

Security groups in OpenStack ...