Allow running docker driver with force on 1 CPU

[afbjorklund]

For running on killercoda

Closes #15608

---

https://killercoda.com/examples/scenario/ubuntu-simple

minikube start --driver=docker

[medyagh]

@afbjorklund does this replace the other PR ? https://github.com/kubernetes/minikube/pull/15610/files

[spowelljr]

@afbjorklund does this replace the other PR ? https://github.com/kubernetes/minikube/pull/15610/files

One is for none driver and one is for docker driver

[afbjorklund]

I'm not sure why it was checked in two (or three?) different places

[spowelljr]

This doesn't seem to be working for me

$ ./out/minikube start --driver docker --force
😄  minikube v1.28.0 on Darwin 13.1 (arm64)
❗  minikube skips various validations when --force is supplied; this may lead to unexpected behavior
✨  Using the docker driver based on user configuration
- Ensure your docker daemon has access to enough CPU/memory resources.
- Docs https://docs.docker.com/docker-for-mac/#resources

⛔  Requested cpu count 2 is greater than the available cpus of 1


⛔  Docker Desktop has less than 2 CPUs configured, but Kubernetes requires at least 2 to be available
💡  Suggestion: 

    1. Click on "Docker for Desktop" menu icon
    2. Click "Preferences"
    3. Click "Resources"
    4. Increase "CPUs" slider bar to 2 or higher
    5. Click "Apply & Restart"
📘  Documentation: https://docs.docker.com/docker-for-mac/#resources

📌  Using Docker Desktop driver with root privileges
👍  Starting control plane node minikube in cluster minikube
🚜  Pulling base image ...
🔥  Creating docker container (CPUs=2, Memory=4000MB) ...

⛔  Exiting due to RSRC_DOCKER_CORES: Docker Desktop has less than 2 CPUs configured, but Kubernetes requires at least 2 to be available
💡  Suggestion: 

    1. Click on "Docker for Desktop" menu icon
    2. Click "Preferences"
    3. Click "Resources"
    4. Increase "CPUs" slider bar to 2 or higher
    5. Click "Apply & Restart"
📘  Documentation: https://docs.docker.com/docker-for-mac/#resources

[spowelljr]

Oh, this is only for Linux specifically?

[afbjorklund]

It was only meant for killercoda "ubuntu"

But Docker Desktop has 2 vCPU by default, right ?

CPUs. By default, Docker Desktop is set to use half the number of processors available on the host machine.

It does need the other patch (#15610), for kubeadm

[afbjorklund]

It can run kind today, since they disable the "preflight" phase

[spowelljr]

It was only meant for killercoda "ubuntu"

But Docker Desktop has 2 vCPU by default, right ?

CPUs. By default, Docker Desktop is set to use half the number of processors available on the host machine.

It does need the other patch, for kubeadm

I just tried setting it to one core for testing purposes

[k8s-ci-robot]

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