We are using the helm chart to bring our own runner and we have a custom image that we use by default in a private registry. To make this work we specified
DOCKER_AUTH_CONFIG in our values.yml and this works fine.
However, when I try to build an image during CI using another image from this registry I get
... ERROR: failed to fetch anonymous token: unexpected status: 403 Forbidden ... failed to solve with frontend dockerfile.v0: failed to build LLB: failed to load cache key: failed to fetch anonymous token: unexpected status: 403 Forbidden
When I add an explicit login to the registry during build this works. Is it expected that I cannot use the runners authorization or do I need to do something to make this work? Run your CI/CD jobs in Docker containers | GitLab does suggest it should just work .