changing vm-driver from hyperkit to another should delete left over

[medyagh]

After user decides to replace hyperkit with another driver, we should delete the left over hyperkit.

to reproduce:

• minikube start --vm-driver=hyperkit

• minikube start --vm-driver=virtualbox

• pgrep hyperkit

the last one should return no more than 1 pid !

@josedonizetti do you have ideas how to tackle this ?

[RA489]

@medyagh Is it happening only for hyperkit with another driver or with another vm-drivers too?

[josedonizetti]

@medyagh Wonder if you got a different output here? When I run two start commands with different drives sequentially I get on the second run:

minikube start --vm-driver=virtualbox
😄  minikube v1.2.0 on darwin (amd64)


⚠️  Ignoring --vm-driver=virtualbox, as the existing "minikube" VM was created using the hyperkit driver.
⚠️  To switch drivers, you may create a new VM using `minikube start -p <name> --vm-driver=virtualbox`
⚠️  Alternatively, you may delete the existing VM using `minikube delete -p minikube`


🏃  Re-using the currently running hyperkit VM for "minikube" ...
⌛  Waiting for SSH access ...
🐳  Configuring environment for Kubernetes v1.15.0 on Docker 18.09.6
🔄  Relaunching Kubernetes v1.15.0 using kubeadm ...
⌛  Verifying: apiserver proxy etcd scheduler controller dns
🏄  Done! kubectl is now configured to use minikube

same thing for kvm2/linux

I don't think we should delete a vm if another start is done with a different driver.

[josedonizetti]

What I think is the problem here is that if we do:

./out/minikube start --vm-driver=kvm2
./out/minikube profile list
|---------|-----------|---------------|-----------|--------------------|
| Profile | VM Driver |    NodeIP     | Node Port | Kubernetes Version |
|---------|-----------|---------------|-----------|--------------------|
| test    | kvm2      | 192.168.39.56 |      8443 | v1.15.0            |
|---------|-----------|---------------|-----------|--------------------|

then do a start using the virtualbox driver:

 ./out/minikube start --vm-driver=virtualbox
./out/minikube profile list
|---------|------------|---------------|-----------|--------------------|
| Profile | VM Driver  |    NodeIP     | Node Port | Kubernetes Version |
|---------|------------|---------------|-----------|--------------------|
| test    | virtualbox | 192.168.39.56 |      8443 | v1.15.0            |
|---------|------------|---------------|-----------|--------------------|

We get the vm-driver as virtualbox although this vm is still on kvm2:

virsh list
 Id    Name                           State
----------------------------------------------------
 10    test                           running

What we need to do here is not set the vm-driver to virtualbox on the second start. Only warn the users that either he creates a new profile, or delete the current profile to use the new driver.

@medyagh ???

[tstromberg]

I believe this was addressed in minikube v1.4, which refuses to hot-swap between drivers.