Unable to pass dnsConfig to self-hosted autoscaling runners

[sammcj]

I'm trying to set dnsConfig on the self-hosted autoscaling runner deployments.

Apologies if I'm simply trying to set it in the wrong place - I'm new to helm and very new to Actions.

Checks

• [?] My actions-runner-controller version (v0.12.7) does support the feature
• [-] I'm using an unreleased version of the controller I built from HEAD of the default branch

To Reproduce

I followed actions-runner-controller.md, using helm for the controller and deploying the runners via a simple kubernetes deployment manifest.

Which errors as it can't find RunnerDeployment.spec.template.spec.dnsConfig:

error: error validating "runnerdeployment.yaml": error validating data: ValidationError(RunnerDeployment.spec.template.spec): unknown field "dnsConfig" in dev.summerwind.actions.v1alpha1.RunnerDeployment.spec.template.spec; if you choose to ignore these errors, turn validation off with --validate=false

Steps to reproduce the behavior:

1. Deploy the self-hosted runner controller using the provided helm chart.
2. Create a deployment.yaml similar to those supplied in actions-runner-controller.md.
3. Add dnsConfig to the deployment.yaml and apply.
4. Try applying the deployment.
5. Experience error above as the CRD doesn't accept RunnerDeployment.spec.template.spec.dnsConfig

Expected behavior

The following k8s deployment manifest (or similar) to work:

apiVersion: actions.summerwind.dev/v1alpha1
kind: RunnerDeployment
metadata:
  name: gha-runner-deployment
spec:
  template:
    spec:
      dnsConfig:
        options:
        - name: ndots     
          value: "1"

and from that dnsConfig should be passed to runner pods which configures /etc/resolv.conf inside containers with the provided options.

Environment:

• Controller Version - 0.19.0
• Deployment Method - Helm
• Helm Chart Version - v0.12.7

Additional Context:

The reason I'm needing to configure this is because it seems with DIND (or really Docker in ContainerD) some base images (such as alpine) incorrectly get ndots:5 configured in /etc/resolv.conf which causes DNS lookup failures inside the container.

information on what ndots is

[mumoshu]

@sammcj Hey! This sounds like a valid feature request. Would you mind submitting a PR like #628 to add the additional pod template field support for Runner and RunnerDeployment resources?

You can also try RunnerSet which is still an unreleased feature, if you could try building a custom build of actions-runner-controller from master branch.

https://github.com/actions-runner-controller/actions-runner-controller#stateful-runners

RunnerSets supports any pod template fields out of the box.

[callum-tait-pbx]

@sammcj FYI https://github.com/rewanthtammana/kubectl-fields this plugin is super helpful for checking if a attribute is part of your deployed CRD set, for example here what it found for the limits attribute:

$ kubectl fields runnerdeployment limits

spec.template.spec.dockerdContainerResources.limits
spec.template.spec.resources.limits
spec.template.spec.volumes.ephemeral.volumeClaimTemplate.spec.resources.limits

[sammcj]

Thanks for confirming this isn't currently possible @mumoshu, I'll submit a PR!

[sammcj]

@callum-tait-pbx that looks really useful! Thank you!

[sammcj]

@mumoshu - Initial crack at it: #764

I've almost certainly missed a few things and the local test suite takes over 40 mins to run which made experimentation a little difficult - I'm hoping Github Actions workflow for PRs has the same coverage.