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<@ULVA73B9P> I can't get `prefect-worker` deployme...
# ask-marvin
m
@Marvin I can't get 
prefect-worker
deployment on my k8s cluster to start a job that gets an image from a private registry. I'm following the Prefect 3.X guide from this page: https://docs.prefect.io/3.0/deploy/infrastructure-examples/kubernetes#deploy-the-flows . This is what I have in my `prefect.yaml`:
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deployments:
- name: "default"
  tags: *common_tags
  schedule: null
  entrypoint: "flows/flow_3_kubernetes_worker.py:hello"
  work_pool:
    name: "kubernetes"
    job_variables:
      image: "{{ build-image.image }}"
      imagePullSecrets:
        - name: private-registry
When I look at the the job details in the UI, I can see 
ImagePullSecrets
being correctly added to the Job Variables section:
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{
  "image": "my-image",
  "imagePullSecrets": [
    {
      "name": "private-registry"
    }
  ]
}
However, the k8s job spec created by the worker has no 
ImagePullSecrets
. I'd spect that to be automatically added to my job by 
prefect-worker
. Already tried multiple worker restarts and deleting/recreating the deployment on prefect.
💯 1
m
It seems that Prefect's handling of Kubernetes jobs for images stored in private registries might not perfectly align with expectations, especially regarding the use of 
ImagePullSecrets
. Although the 
prefect-worker
should theoretically add 
ImagePullSecrets
automatically, there are some known issues and limitations documented. 1. Known Issues and Workarounds: There is an open issue discussing the difficulty in specifying private registry credentials for Kubernetes workers on GitHub. It provides insights into how others are working around this limitation by manually editing the Kubernetes job configuration to include 
imagePullSecrets
. Here's a quick excerpt from the issue:
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json
   "imagePullSecrets": [
       {
         "name": "private-registry"
       }
     ]
Consider manually setting the 
imagePullSecrets
in the advanced job configuration, akin to this setup. 2. Documentation Insights: The Prefect documentation does not explicitly list an automatic method for handling private registry authentication outside of manually configuring more advanced job templates, as you can see from this excerpt. 3. Possible Solution: If 
imagePullSecrets
are not auto-added, you might want to manually modify your Kubernetes job configuration to include them. There's a detailed example in the GitHub issue linked above that could guide you through a direct modification. Marvin's slightly paranoid note: Isn't it delightful how some systems choose a most unique moment to remind us of their quirks? It's almost by design. If you'd like to explore more or have further questions, feel free to ask.
It looks like you're having an issue with getting the 
ImagePullSecrets
correctly configured in your Kubernetes deployment for Prefect 3.x. This is a known challenge when using Prefect workers on Kubernetes, especially when working with private registries. Based on what I found, you might need to manually configure or double-check the job template used by your Kubernetes work pool. Here are some steps you might consider: 1. Custom Job Template: You can modify the base job template to include the 
imagePullSecrets
manually. This is done by editing the JSON configuration of the job template within the Prefect UI under the "Advanced" settings tab. Ensure that the 
ImagePullSecrets
field is correctly added under the 
jobConfiguration
part of your job template. 2. Double-check Values: Ensure that the secret name in your Kubernetes cluster matches exactly with the one you expect Prefect to use. Sometimes a simple typo might cause the secret to not be applied correctly. 3. Configuration and Permissions: Verify that the Prefect worker has the necessary permissions to modify and apply these settings on your Kubernetes cluster. 4. Consult Prefect's Community or Documentation: It might also be useful to reach out to the Prefect community for shared experiences regarding this common issue. Here are some helpful links: - General guidance on running flows on Kubernetes with Prefect: https://docs.prefect.io/3.0/deploy/infrastructure-examples/kubernetes - An issue related to job execution might provide some insights: Issue link Unfortunately, no specific instructions appear in the resources regarding automatic adding of 
ImagePullSecrets
by `prefect-worker`; it seems most guidance revolves around manual configuration. So feel free to grumble gently at your machine. If you find persistent issues, consider raising this on their GitHub Issues page for more technical assistance.
It seems like the issue of 
ImagePullSecrets
not being applied during the deployment of a Prefect worker job on Kubernetes might stem from how job specifications are handled in Prefect configuration. Here's what you could try: 1. Manual Inclusion: It might be necessary to manually specify 
imagePullSecrets
in your job template. The link you provided discusses how Kubernetes work pools allow modifying the job template. Consider editing the base job JSON template in the Prefect UI to include 
imagePullSecrets
explicitly. 2. Ensure Compatibility: Double-check that Prefect and your Kubernetes version are compatible. Prefect documentation suggests using Kubernetes versions 1.26.0 or newer. Any discrepancies might lead to unexpected behavior during job creation. 3. Prefect Version Check: Ensure you're using a version of Prefect that has the feature or support for kube job specs with 
imagePullSecrets
. Although the Prefect documentation aligned with your setup doesn't specifically mention automated inclusion of 
imagePullSecrets
, manually configuring the job template is still a sound workaround. You can refer to the Prefect documentation here which outlines the general setup for Kubernetes infrastructure. As for further references, you might find this GitHub issue informative, as it discusses related configuration errors: GitHub Issue #15259. Although the provided solutions require a bit of manual tweaking, they offer a reliable path forward until any automated support is more robustly integrated into Prefect. If you're feeling like the universe conspires against your deployments, remember: the solution might just be one YAML field away!
m
Ok, so one of the links here helped me. I had to go into my worker pool > edit > "Base Job Template" > Advanced. I had to add the 
imagePullSecrets
section inside the `"job_manifest" section of the JSON:
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"job_manifest": {
      "kind": "Job",
      "spec": {
        "template": {
          "spec": {
            "containers": [
              {
                "env": "{{ env }}",
                "args": "{{ command }}",
                "name": "prefect-job",
                "image": "{{ image }}",
                "imagePullPolicy": "{{ image_pull_policy }}"
              }
            ],
            "completions": 1,
            "parallelism": 1,
            "restartPolicy": "Never",
            "imagePullSecrets": [
              {
                "name": "private-registry"
              }
            ],
            "serviceAccountName": "{{ service_account_name }}"
          }
        },
        "backoffLimit": 0,
        "ttlSecondsAfterFinished": "{{ finished_job_ttl }}"
      },
I suspect that 
Job Variables
would affect anything within 
job_manifest > template > spec > containers
, but 
imagePullSecrets
is at a higher level. I don't like the ergonomics here (since it wouldn't allow me to use multiple private registries for jobs within the same worker-pool), but this at least lets me move forward with my experiments. Thank you
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