Terraform iPad VM

Create a VM on Google Cloud to do dev work on an iPad.

Why anyone wants to do this:

• Traveling with two laptops (work and personal) is clunky
• I can use the iPad as my social consumption device and developer laptop
• It's fun to play with tech and push the limits

Assumptions

• The following CLI tools installed on a non-iPad Linux workstation:
  • terraform
  • gcloud
• A (free) Tailscale account setup for WireGuard VPN management.
• An iPad
  • with the (free) Tailscale client installed for VPN access.
  • with the ($20) blink.sh app installed for terminal access.

Overview

Setup

On your non-iPad Linux workstation clone the repo

git clone git@github.com:jimangel/Terraform-iPad-VM.git
cd Terraform-iPad-VM

Get a one-off Tailscale authorization key

Navigate to https://login.tailscale.com/admin/authkeys. Choose 'Create a new key' > 'One-off key'

Export the key as a Terraform variable; replacing YOUR_KEY with the key provided.

export TF_VAR_tailscale_key=YOUR_KEY

The key auto-authenticates your server to Tailscale upon creation. It uses GCP's startup scripts and Terraform's template (see startup_script.tpl for more info).

The startup script does a lot of stuff specific to my use case. Please review before deploying.

Create the VM

Setup the gcloud cli; replacing PROJECT_ID with your project ID.

gcloud auth login

gcloud config set project PROJECT_ID

Export the project ID as a Terraform variable

export TF_VAR_project_id=$(gcloud config get-value core/project 2>/dev/null)

Export GCP auth token (valid for 1 hour) and project for Terraform

export GOOGLE_OAUTH_ACCESS_TOKEN="$(gcloud auth print-access-token)"
export GOOGLE_PROJECT="$(gcloud config get-value project)"

Dry-run to initialize and plan the deployment

terraform init && terraform plan

Create the VM*

terraform apply

*It might take a few minutes for the startup script (provisioning Tailscale) to run after the VM starts.

Setup GCP SSH access from the iPad

On your iPad, use Blink to create an ssh key. ssh-keygen is available, so we can create our SSH keys.

Replace USERNAME with your preferred username.

ssh-keygen -t rsa -b 4096 -C “USERNAME”

# press 'Enter' to take defaults

# copy to clipboard
cat ~/.ssh/id_rsa.pub | pbcopy

Add SSH public key to GCP

Swipe out of blink.sh and open a browser and log in to console.cloud.google.com. Navigate to:

• Compute Engine
• VM instances
• click on ipad-cloud > Edit
• Under "You have 0 SSH keys" > "Show and edit"
• Paste content of public key by taping in the box and long holding > "Paste"
• Save (at the bottom)

Add SSH private key to blink.sh

Add the key:

• type cat ~/.ssh/id_rsa | pbcopy
• type config
• Keys > "+"
• Import from clipboard
• (enter a name for the key) > Save

Add GCP host to blink.sh

Use the VM's IP from Tailscale to replace the IP_ADDRESS.

• Hosts > "+"
• Host: gcp-vm
• HostName: IP_ADDRESS
• Key: (switch None to your key) > Go back and Save

Test connectivity

Log in to the server using mosh (a mobile friendly SSH terminal supported by blink.sh):

mosh gcp-vm

# accept fingerprint if asked
# accept disk write access if asked

You should be in! 🎉

Extra stuff

Any parameter in this Terraform file can be overwritten by exporting a variable.

Run in a different zone

Find the region closest to you with http://www.gcping.com/ and set the Terraform zone variable. Tip: find the zones with gcloud compute zones list --filter=region:REGION_ID

export TF_VAR_availability_zone=YOUR_ZONE

Use a different VM name

export TF_VAR_vm_name=YOUR_NAME

Use a different machine type

Search machine types with gcloud compute machine-types list --zones=YOUR_ZONE

# Defaults to: e2-medium
export TF_VAR_machine_type=YOUR_TYPE

# e2 instances from cheapest to more expensive:
# - e2-micro (2x1GB shared CPU)
# - e2-small (2x2GB shared CPU)
# - e2-medium (2x4GB shared CPU)
# - e2-standard-2 (2x8GB dedicated CPU)

Troubleshooting

• Check the output of startup_script.

  sudo journalctl -u google-startup-scripts.service
  

• Delete Hosts or Keys in blink.sh navigate to them by typing config and then swipe left > Delete.

• Expose kubectl commands over tailscale:

  kubectl port-forward deployment/kubernetes-dashboard -n kube-system 8443:8443 --address `Tailscale_IP`
  

  Navigate to: Tailscale_IP:8443

• Forward / tunnel ports to your ipad

  Use two fingers to tap your blink.sh shell (opens a new terminal). Change between the terminals by swiping right or left. Run:

  ssh -L LOCALPORT:localhost:REMOTEPORT <REMOTE IP>
  # ex: ssh -L 1313:localhost:1313 192.168.1.250
  

  As long as that terminal session is open, the tunnel will exist.