Trying to start minikube on mac. Virtualization is being provided by VirtualBox.

    $ minikube start
      minikube v1.1.0 on darwin (amd64)
      Creating virtualbox VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
      Configuring environment for Kubernetes v1.14.2 on Docker 18.09.6
    ❌  Unable to load cached images: loading cached images: loading image /Users/paul/.minikube/cache/images/k8s.gcr.io/kube-proxy_v1.14.2: Docker load /tmp/kube-proxy_v1.14.2: command failed: docker load -i /tmp/kube-proxy_v1.14.2
    stdout: 
    stderr: open /var/lib/docker/image/overlay2/layerdb/tmp/write-set-542676317/diff: read-only file system
    : Process exited with status 1

      Failed to setup certs: pre-copy: command failed: sudo rm -f /var/lib/minikube/certs/ca.crt
    stdout: 
    stderr: rm: cannot remove '/var/lib/minikube/certs/ca.crt': Input/output error
    : Process exited with status 1

  Sorry that minikube crashed. If this was unexpected, we would love to hear from you:
  https://github.com/kubernetes/minikube/issues/new

Trying minikube delete followed by minikube start produces the same issue.

Docker is running and is signed in.

I also deleted all machines in virtualbox after minikube delete and still get the same result.