Error creating new host: json: cannot unmarshal bool into Go struct field Driver.Virtio9p

Your 1.34.0 version of Minishift is currently tested against docker-machine-driver-xhyve version 0.3.3. and has compatibility issues with the recently deployed docker-machine-driver-xhyve v0.4.0.

The solution for me was to uninstall the docker-machine-driver-xhyve 0.4.0 driver and install the old and tested 0.3.3:

https://github.com/machine-drivers/docker-machine-driver-xhyve/releases/tag/v0.3.3

$ brew uninstall docker-machine-driver-xhyve
$ brew edit docker-machine-driver-xhyve

Change the tag: and revision: references to:

class DockerMachineDriverXhyve < Formula
  desc "Docker Machine driver for xhyve"
  homepage "https://github.com/machine-drivers/docker-machine-driver-xhyve"
  url "https://github.com/machine-drivers/docker-machine-driver-xhyve.git",
      :tag      => "v0.3.3",
      :revision => "7d92f74a8b9825e55ee5088b8bfa93b042badc47"
  revision 2

brew install as usual:

$ brew install docker-machine-driver-xhyve

$ minishift start 
-- Starting profile 'minishift'
-- Check if deprecated options are used ... OK
-- Checking if https://github.com is reachable ... OK
-- Checking if requested OpenShift version 'v3.11.0' is valid ... OK
-- Checking if requested OpenShift version 'v3.11.0' is supported ... OK
-- Checking if requested hypervisor 'xhyve' is supported on this platform ... OK
-- Checking if xhyve driver is installed ...
   Driver is available at /usr/local/bin/docker-machine-driver-xhyve
   Checking for setuid bit ... OK
-- Checking the ISO URL ... OK
-- Checking if provided oc flags are supported ... OK
-- Starting the OpenShift cluster using 'xhyve' hypervisor ...
-- Minishift VM will be configured with ...
   Memory:    4 GB
   vCPUs :    2
   Disk size: 20 GB
-- Starting Minishift VM ...................... OK
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