I have been using Local by Flywheel and really enjoying it. It does two things:

1. You can stand up a development version of a WordPress site on your laptop and horse around with it. It’s fast, you can make experiments, and if it blows up, you can simply regenerate in a minute or two.
2. Using the (paid) Flywheel hosting, you can transfer your local dev server to their public hosting, and you’re on the air.

I have not used this latter facility, but I’m here to tell you that the first part is pretty slick.

But… I went away from Local by Flywheel for a month or so, then came back to start working on a new site. When I wanted to start it up, I saw a succession of messages stating that it was “Regenerating Machine Certificates” and that “Local detected invalid Docker Machine TLS certificate sand is fixing them now.” This looped apparently forever, and wouldn’t work. Here’s my report on their community forum.

After considerable searching, I found a procedure from one of the developers that seems to do the trick. It involves downloading a new version of the Boot2Docker ISO file, and letting the system re-provision itself. The process involved a) Creating an alias (“local-docker-machine”) for the “Local by Flywheel”s docker-machine binary; b) issuing a series of commands to that alias:

local-docker-machine stop local-by-flywheel
rm -rf ~/.docker/machine/certs
local-docker-machine create local-cert-gen
local-docker-machine start local-by-flywheel
local-docker-machine regenerate-certs -f local-by-flywheel
local-docker-machine rm -f local-cert-gen

These steps caused Local by Flywheel to recognize that the Boot2Docker ISO was out of date. It triggered a download of the new version, and gave the output below. When it completed Local by Flywheel worked as expected. Whew!

bash-3.2$ alias local-docker-machine="/Applications/Local\ by\ Flywheel.app/Contents/Resources/extraResources/virtual-machine/vendor/docker/osx/docker-machine"
bash-3.2$
bash-3.2$ local-docker-machine stop local-by-flywheel; rm -rf ~/.docker/machine/certs; local-docker-machine create local-cert-gen; local-docker-machine start local-by-flywheel; local-docker-machine regenerate-certs -f local-by-flywheel; local-docker-machine rm -f local-cert-gen;
Stopping "local-by-flywheel"...
Machine "local-by-flywheel" is already stopped.
Creating CA: /Users/richb/.docker/machine/certs/ca.pem
Creating client certificate: /Users/richb/.docker/machine/certs/cert.pem
Running pre-create checks...
(local-cert-gen) Default Boot2Docker ISO is out-of-date, downloading the latest release...
(local-cert-gen) Latest release for github.com/boot2docker/boot2docker is v18.09.1
(local-cert-gen) Downloading /Users/richb/.docker/machine/cache/boot2docker.iso from https://github.com/boot2docker/boot2docker/releases/download/v18.09.1/boot2docker.iso...
(local-cert-gen) 0%....10%....20%....30%....40%....50%....60%....70%....80%....90%....100%
Creating machine...
(local-cert-gen) Copying /Users/richb/.docker/machine/cache/boot2docker.iso to /Users/richb/.docker/machine/machines/local-cert-gen/boot2docker.iso...
(local-cert-gen) Creating VirtualBox VM...
(local-cert-gen) Creating SSH key...
(local-cert-gen) Starting the VM...
(local-cert-gen) Check network to re-create if needed...
(local-cert-gen) Waiting for an IP...
Waiting for machine to be running, this may take a few minutes...
Detecting operating system of created instance...
Waiting for SSH to be available...
Detecting the provisioner...
Provisioning with boot2docker...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
Checking connection to Docker...
Docker is up and running!
To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: /Applications/Local by Flywheel.app/Contents/Resources/extraResources/virtual-machine/vendor/docker/osx/docker-machine env local-cert-gen
Starting "local-by-flywheel"...
(local-by-flywheel) Check network to re-create if needed...
(local-by-flywheel) Waiting for an IP...
Machine "local-by-flywheel" was started.
Waiting for SSH to be available...
Detecting the provisioner...
Started machines may have new IP addresses. You may need to re-run the `docker-machine env` command.
Regenerating TLS certificates
Waiting for SSH to be available...
Detecting the provisioner...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
About to remove local-cert-gen
WARNING: This action will delete both local reference and remote instance.
Successfully removed local-cert-gen