What
T403125: Investigate WMCS Magnum for GitLab runners is complete and shows that we can feasibly run gitlab-cloud-runner on WMCS using Magnum. Let's push forward with the migration from DigitalOcean to WMCS.
Why
DigitalOcean has provided us with a flexible k8s based platform for our GitLab CI runners for some time. However, maintaining a network of runners on third-party infrastructure has its downsides.
- Users needing to access services/resources from other WMCS projects have had to resort to using the Docker-based WMCS runners.
- Requests to services on the WMCS or WMF networks are subject to throttling and it has been difficult to identify/exempt traffic from DO.
- Email relaying (for notifications) from DO has been difficult.
- Service endpoints rely on non-WMF hostnames (e.g. registry.cloud.releng.team).
- The level of support from DO hasn't been bad per se, but with WMCS we have a dedicated WMF team to work with.
With WMCS/OpenStack Magnum we get the flexibility of a Tofu-configurable k8s provider without the above drawbacks.