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<@ULVA73B9P> I created a work pool of type kuberne...
# ask-marvin
u
@Marvin I created a work pool of type kubernetes in prefect v3, when passing command as job variable, it is mapping to args in job spec and there is not "command" in job spec
m
✅ thought for 39.4 seconds
Based on my research and understanding of the issue, I can explain what's happening with the command and args in Kubernetes work pools: 1. In Kubernetes work pools, when you specify a 
command
in the job variables, it gets mapped to the 
args
field in the Kubernetes job spec rather than the 
command
field. This is because of how Kubernetes handles command execution in containers. 2. In Kubernetes, there are two related fields: - 
command
(in Kubernetes): Overrides the container's ENTRYPOINT - 
args
(in Kubernetes): Overrides the container's CMD 3. When you specify a command in Prefect's job variables, it's treating this as arguments to be passed to the container's existing ENTRYPOINT, which is why they appear in the 
args
section of the job spec. To handle this, you have a few options: 1. If you need to override both the ENTRYPOINT and arguments, you can specify both in your job variables using the full job spec:
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["/bin/sh", "-c"]
              args: ["your command here"]
2. If you just want to pass arguments to the existing ENTRYPOINT, continue using the 
command
parameter as you are now, understanding that it will map to 
args
in the job spec. 3. You can also modify the base job template of your work pool to set a default command if needed. To verify or modify your work pool's configuration, you can use:
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bash
prefect work-pool show "your-pool-name"
Would you like me to help you with any specific configuration you're trying to achieve with your Kubernetes work pool? It would be helpful if you could share: 1. What command you're trying to run 2. What behavior you're expecting 3. The current base job template you're using (if any)
u
@Marvin i need to overwrite both entrypoint and args, what should be the values for args and command? I tried but this fails to create a prefect flow run
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- args:                                                                                                                                                                                  │
│     - prefect                                                                                                                                                                              │
│     - flow-run                                                                                                                                                                             │
│     - execute                                                                                                                                                                              │
│     command:                                                                                                                                                                               │
│     - /bin/sh                                                                                                                                                                              │
│     - -c
m
✅ thought for 41.2 seconds
Based on my research and understanding of Kubernetes and Prefect, here's the correct way to configure both the command and args for your Kubernetes work pool: 1. For a Prefect flow run to execute properly in Kubernetes, you need to ensure the container runs the Prefect command correctly. Here's the proper configuration:
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["python", "-m"]
              args: ["prefect.engine"]
Or if you need to use a shell:
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["/bin/sh", "-c"]
              args: ["python -m prefect.engine"]
Key points to understand: 1. The 
command
field defines the executable and initial arguments (equivalent to ENTRYPOINT in Docker) 2. The 
args
field provides the remaining arguments (equivalent to CMD in Docker) 3. Both fields expect arrays of strings 4. Make sure the indentation is correct - each level should be properly nested Common issues to avoid: - Don't put the entire command in the 
command
field - Don't mix command and args in the same field - Ensure proper YAML formatting with correct indentation - Make sure the Python environment in your container has Prefect installed Would you like me to help you troubleshoot your specific use case? It would be helpful if you could share: 1. The complete job configuration you're trying to use 2. Any error messages you're seeing 3. The base image you're using for your container
u
@Marvin i added the following
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- args:                                                                                                                                                                                  │
│     - python3                                                                                                                                                                              │
│     - -m                                                                                                                                                                                   │
│     - prefect.engine                                                                                                                                                                       │
│     command:                                                                                                                                                                               │
│     - /bin/sh                                                                                                                                                                              │
│     - -c
but as expected, it did not run anything 
stream closed EOF for prefect/prefect-test-5dx24-mpmm9 (prefect-job)
m
✅ thought for 28.0 seconds
Based on the research, here are two approaches you can try: 1. Using shell with combined Python command (recommended):
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["/bin/sh", "-c"]
              args: ["python3 -m prefect.engine"]
2. Direct Python execution (alternative approach):
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["python3"]
              args: ["-m", "prefect.engine"]
To troubleshoot the "stream closed EOF" error: 1. Make sure your container has Python3 and Prefect installed 2. Check if you can see any container logs before the EOF:
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bash
   kubectl logs <pod-name> --previous
3. Verify the container's environment:
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bash
   kubectl describe pod <pod-name>
Would you like me to help you troubleshoot further? If so, please provide: 1. The complete job configuration you're using 2. The output of 
kubectl describe pod
for the failed pod 3. Any logs you can see from the container before it exits
u
@Marvin this way erroring with python3: can't open file '/app/prefect.engine': [Errno 2] No such file or directory
m
✅ thought for 9.5 seconds
Ah, I see the issue now. The error indicates that Python is interpreting "-m prefect.engine" as a file path rather than a module specification. This is happening because the shell is not properly parsing the Python command. Let me help you fix this. Here's the correct configuration:
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yaml
job_variables:
  job_spec:
    spec:
      template:
        spec:
          containers:
            - command: ["python3", "-m"]
              args: ["prefect.engine"]
Key points about this configuration: 1. We separate the Python interpreter and 
-m
flag into the 
command
array 2. The module name 
prefect.engine
goes into the 
args
array 3. We don't use 
/bin/sh -c
in this case as we want to directly invoke Python This configuration ensures that: - Python correctly interprets the 
-m
flag to load a module - The module path 
prefect.engine
is properly passed as an argument - There's no shell interpretation that could cause parsing issues If you're still seeing issues, let's verify a few things: 1. Make sure Prefect is installed in your container:
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yaml
   job_variables:
     job_spec:
       spec:
         template:
           spec:
             containers:
               - command: ["python3", "-c"]
                 args: ["import prefect; print(prefect.__version__)"]
2. Check the Python path in your container:
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yaml
   job_variables:
     job_spec:
       spec:
         template:
           spec:
             containers:
               - command: ["python3", "-c"]
                 args: ["import sys; print(sys.path)"]
Would you like me to help you troubleshoot further? If so, please: 1. Try the corrected configuration I provided above 2. If it doesn't work, share any new error messages you see 3. Let me know which Prefect image you're using for the container
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