Updated on 2024-07-16 GMT+08:00

Security Group

Overview

A security group is a collection of access control rules for cloud resources, such as cloud servers, containers, and databases, that have the same security protection requirements and that are mutually trusted. After a security group is created, you can configure access rules that will apply to all cloud resources added to this security group.

For more information about security groups, see security groups.

If two FlexusX instances are in the same security group but in different VPCs, the instances cannot communicate with each other. To enable communications between the two instances, connect the two VPCs first. For details, see Connecting VPCs.

Security Group Rules

After a security group is created, you can add rules to it. A rule applies either to inbound traffic (ingress) or outbound traffic (egress). Any FlexusX instances added to the security group are protected by the rules of that group. For details about more configuration examples, see Security Group Examples.

You can create a custom security group or use the default one provided by the system. The default security group permits all outbound traffic and denies inbound traffic. FlexusX instances in a security group can communicate with each other.

Table 1 Default security group rules

Direction

Action

Type

Protocol & Port

Source/Destination

Description

Inbound

Allow

IPv4

All

Source: default security group (default)

Allows IPv4 instances in the security group to communicate with each other using any protocol over any port.

Inbound

Allow

IPv6

All

Allows IPv6 instances in the security group to communicate with each other using any protocol over any port.

Outbound

Allow

IPv4

All

Destination: 0.0.0.0/0

Allows access from instances in the security group to any IPv4 address over any port.

Outbound

Allow

IPv6

All

Destination: ::/0

Allows access from instances in the security group to any IPv6 address over any port.

Security Group Constraints

  • By default, you can create up to 100 security groups in your cloud account.
  • By default, you can add up to 50 rules to a security group.
  • For better network performance, you are advised to associate no more than five security groups with a FlexusX instance or supplementary network interface.
  • You can add up to 20 instances to a security group at a time.
  • You can add up to 1,000 instances to a security group.