K8s plugin: Add --volume and --mount options support

[shoce]

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Motivation and Context

To allow bind mounts from host machine into k8s container.

Issue #2159

Testing

• Tested locally
• Added/updated tests
• Added/updated docs

[shoce]

Issue #2159

[egernst]

@shoce - thanks for the PR. I haven't reviewed in detail yet, but I have an initial concern of how we would manage this in a multi-node configuration.

[shoce]

@shoce - thanks for the PR. I haven't reviewed in detail yet, but I have an initial concern of how we would manage this in a multi-node configuration.

sorry, i have no idea. can you please elaborate on what can go wrong in a multi-node configuration? multi-node in our case is still running on the same host machine right?

[katiewasnothere]

Hi @shoce I have an open PR at #2276 for adding multi node support. This PR is stalled right now but can give a sense of what the multi node support will look like.

For your PR here, in the multi node case, would all of the nodes in the cluster that are created during k8s create also have the volume mounted to them?

[shoce]

Hi @shoce I have an open PR at #2276 for adding multi node support. This PR is stalled right now but can give a sense of what the multi node support will look like.

Thanks, i got the idea. That multi-node implementation does not look like something i would like to use - because it is a creation of few containers with only one cli command and need to provide all the configuration via arguments (and env vars possibly). A command to create a worker node and connect it to a specified control plane node would be much more handy to me.

For your PR here, in the multi node case, would all of the nodes in the cluster that are created during k8s create also have the volume mounted to them?

With your current PR i would say yes, like with --cpus, --memory and --node-image options, --volume and --mount options would apply to all of them.

[shoce]

@egernst @katiewasnothere

Also now seeing that you are working on multi-node cluster creation, I am thinking if we could have a command to add/remove volumes, mounts and published ports on existing (stopped) containers? Would it be a more flexible way?

Like:

• add --start option to k8s create which will be off by default
• container k8s create without --start
• add volumes, mounts, published ports on the created container(s)
• container start for the control plane and worker nodes

What do you think about this?