Identifying common automation requirements
Establishing a runner depends on what types of images you’ll be building and where. Runners will connect to your GitHub or GitLab instance to monitor a repository for event hooks. The advantage of this is that no ingress ports must be open on your network or firewall. A runner service will simply establish secure API access to your GitHub or GitLab instance and listen for events such as a merge or commit on a certain branch. This is the most basic form of CI, which is actually sufficient for most Packer tasks.
What type of runner you need depends on what types of images you will build. Building cloud images often relies only on API calls and can be done from just about any environment. A runner service may be a container, a VM, a physical machine, or a managed service provided by GitHub or GitLab.
If building remotely in a cloud provider, any runner should suffice. Since the builder is only making API calls to external resources...
