Security Groups form the base primitive with which to build advanced networking setups on Exoscale as we previously demonstrated in our bastion article and our behind the scenes article.

Today we are thrilled to announce the general availability of External source support in Security Groups.

Current situation

As a quick reminder, Security Groups have two key components:

  • A list of rules to apply to members of the group
  • A list of members in the group

Having these two components in Security Group definition allows for instance to create rules which let through traffic for all members of a specific group. Conversely, the list of members is derived from the list of instances belonging to the group.

Enabling more

A common request to enable Security Groups to natively work well with external infrastructure is to have the ability to add CIDRs to the list of sources, allowing them to become part of the authorized CIDRs when rulesets are actually applied on target virtual machines.

This enables not only Exoscale instances or nested security groups but also those external sources to be part of a definition.

Taking it for a tour

Let’s assume we are following the procedure laid out in our bastion article but we would like to also authorize our fictional VPN exit IP as an authorized source.

This would involve adding the IP to the management Security Group:

exo compute security-group source add management
 ✔ Adding Security Group source 3s
│  SECURITY GROUP  │                                      │
│ ID               │ be5f0364-d146-4578-b5fb-faf648f02481 │
│ Name             │ management                           │
│ Description      │                                      │
│ Ingress Rules    │ -                                    │
│ Egress Rules     │ -                                    │
│ External Sources │                      │


you can shorten exo compute security-group to exo c sg

Let’s now make sure that the external source was added:

exo compute security-group show management

Use Exoscale networks as sources

A first use-case application of this new feature is to enable CIDRs from Exoscale sources such as the IPs of a full zone to be used in a security group. For this purpose we are also introducing the official publication of our IP sources as both a JSON file and Geofeed format compliant with RFC 8805 from August 2020.

Those lists are officially maintained and can be consumed by your favorite configuration management tools such as Terraform.

What’s next

While this facility is already useful today and fully available in the Exoscale API and command-line tool, we intend to follow-up with the following complementing features:

  • Web portal integration.
  • Terraform support.
  • A number of public groups to represent Exoscale sources (zone ranges, healthcheck monitor ranges, SOS endpoint ranges amongst others) without having to parse our JSON file.