[Feature] Expose generated ray start command for worker and head nodes.

[kevingreer]

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• I had searched in the issues and found no similar feature requirement.

Description

KubeRay generates a ray start command to that is executed to start the cluster head node and cluster worker nodes. In a RayService Kubernetes config when specifying the head and worker pod templates, you can add a command field, and that command will be prepended to the generated ray start command, like $CUSTOM_CMD && $GENERATED_CMD. The code for this functionality is here.

This issue requests a feature that allows $GENERATED_CMD to be exposed to the custom command specified in the k8s config. After this feature is implemented, a person would be able to use the KubeRay generated ray start command within their custom command specified in their pod templates.

Use case

I have a binary that wraps arbitrary shell commands. This binary provides some general functionality useful for all services at my company, such as piping logs to our various logging systems. It is run like so:

./wrapper-binary --command "$CMD"

where $CMD can be any arbitrary command. For the use case of this issue, I would like $CMD to be ray start command generated by KubeRay.

Related issues

No response

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

[hongchaodeng]

@kevingreer Thanks for putting this together!

We are now in the final stage of releasing v1.0. Will get back on this once v1.0 is released!

[findmyway]

Any progress on this?

It seems the command is prepended to the Args field.

    Command:
      /bin/bash
      -lc
      --
    Args:
       /usr/local/bin/custom.sh  && ulimit -n 65536; ray start --head  --dashboard-host=0.0.0.0  --metrics-export-port=8080  --block  --num-cpus=1

We'd like to apply it to before the ray start command.

[kevin85421]

I will work on this issue this week.

[kevin85421]

We'd like to apply it to before the ray start command.

@findmyway Do you mean ulimit -n 65536; /usr/local/bin/custom.sh; ray start --head --dashboard-host=0.0.0.0 --metrics-export-port=8080 --block --num-cpus=1? Thanks!

[findmyway]

We'd like to apply it to before the ray start command.

@findmyway Do you mean ulimit -n 65536; /usr/local/bin/custom.sh; ray start --head --dashboard-host=0.0.0.0 --metrics-export-port=8080 --block --num-cpus=1? Thanks!

For my case, I mean ulimit -n 65536; /usr/local/bin/custom.sh ray start --head --dashboard-host=0.0.0.0 --metrics-export-port=8080 --block --num-cpus=1

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More details about my usage.

I'm using micromamba in a custom docker image. It has an entrypoint.sh to activate runtime environment ref.