External driver, for cloud and physical

[afbjorklund]

Description

Add a generic driver for external virtual machines and physical servers.

It is similar to running ssh, but includes all the Lima features like agent.

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The user is supposed to have an existing server, with key-based ssh login.

Previously it was hardcoding 127.0.0.1 as the hostname

Host keys are being used (and should be set up), to verify the external server.

Previously it was hardcoding StrictHostKeyChecking=no

A guest-install command is added, to install lima-guestagent and nerdctl-full.

The external machine lifecycle (boot/reboot/etc) is managed outside of Lima.

---

• 2000

• 2028

Tested with Digital Ocean, and with Raspberry Pi.

Note: this driver does not create cloud instances.

• https://github.com/lima-vm/lima/discussions/2029
• docker machine cloud drivers (archived 2019)

[afbjorklund]

The hardware resources are specified by the user, matching the external:

vmType: ext

arch: "aarch64"
cpus: 4
memory: 512MiB
disk: 32GiB

mounts:
- location: "~"
- location: "/tmp/lima"
  writable: true

ssh:
  address: raspberrypi.local

The OS installation is supposed to be aligned, but is not using the "images".

e.g. you would use the cloud web interface or the SD card image for Ubuntu

[afbjorklund]

Note that since machine start and stop are handled externally, it only affects the hostagent.

The user is supposed to install and start the guestagent, and to install containerd/buildkitd.

start

INFO[0000] Using the existing instance "raspberrypi"    
INFO[0000] Starting the instance "raspberrypi" with VM driver "ext" 
INFO[0001] [hostagent] hostagent socket created at /home/anders/.lima/raspberrypi/ha.sock 
INFO[0001] SSH Local Port: 22                           
INFO[0001] [hostagent] Waiting for the essential requirement 1 of 3: "ssh" 
INFO[0002] [hostagent] The essential requirement 1 of 3 is satisfied 
INFO[0002] [hostagent] Waiting for the essential requirement 2 of 3: "sshfs binary to be installed" 
INFO[0003] [hostagent] The essential requirement 2 of 3 is satisfied 
INFO[0003] [hostagent] Waiting for the essential requirement 3 of 3: "/etc/fuse.conf (/etc/fuse3.conf) to contain \"user_allow_other\"" 
INFO[0003] [hostagent] The essential requirement 3 of 3 is satisfied 
INFO[0003] [hostagent] Mounting "/home/anders" on "/home/anders" 
INFO[0004] [hostagent] Mounting "/tmp/lima" on "/tmp/lima" 
INFO[0004] [hostagent] Running system provision 1 of 2  
INFO[0005] [hostagent] Running user provision 2 of 2    
INFO[0005] [hostagent] Waiting for the optional requirement 1 of 4: "systemd must be available" 
INFO[0005] [hostagent] Forwarding "/run/lima-guestagent.sock" (guest) to "/home/anders/.lima/raspberrypi/ga.sock" (host) 
INFO[0005] [hostagent] The optional requirement 1 of 4 is satisfied 
INFO[0005] [hostagent] Waiting for the optional requirement 2 of 4: "containerd binaries to be installed" 
INFO[0005] [hostagent] The optional requirement 2 of 4 is satisfied 
INFO[0005] [hostagent] Waiting for the optional requirement 3 of 4: "user probe 1/2" 
INFO[0005] [hostagent] The optional requirement 3 of 4 is satisfied 
INFO[0005] [hostagent] Waiting for the optional requirement 4 of 4: "user probe 2/2" 
INFO[0005] [hostagent] The optional requirement 4 of 4 is satisfied 
INFO[0005] [hostagent] Waiting for the guest agent to be running 
INFO[0005] [hostagent] Guest agent is running           
INFO[0005] READY. Run `limactl shell raspberrypi` to open the shell. 

stop

INFO[0000] Sending SIGINT to hostagent process 9881     
INFO[0000] Waiting for the host agent and the driver processes to shut down 
INFO[0000] [hostagent] Received SIGINT, shutting down the host agent 
INFO[0000] [hostagent] Shutting down the host agent     
INFO[0000] [hostagent] Stopping forwarding "/run/lima-guestagent.sock" (guest) to "/home/anders/.lima/raspberrypi/ga.sock" (host) 
INFO[0000] [hostagent] Unmounting "/home/anders"        
INFO[0000] [hostagent] Unmounting "/tmp/lima"           

The external server keeps running, including lima-guestagent and friends.

Now also includes support for provisioning, as shown in the above output.

provision:
- mode: system
  script: |
    #!/bin/sh
    touch /tmp/foo
- mode: user
  script: |
    #!/bin/bash
    set -eux -o pipefail
    touch /tmp/bar
probes:
- script: |
    #!/bin/bash
    set -eux -o pipefail
    if ! timeout 10 bash -c "until test -e /tmp/foo >/dev/null 2>&1; do sleep 3; done"; then
      echo >&2 "foo is not touched yet"
      exit 1
    fi
- script: |
    #!/bin/bash
    set -eux -o pipefail
    if ! timeout 10 bash -c "until test -e /tmp/bar >/dev/null 2>&1; do sleep 3; done"; then
      echo >&2 "bar is not touched yet"
      exit 1
    fi

[afbjorklund]

Changed output for non-localhost:

INFO[0001] SSH Local Port: 22                           

Into a slightly more interesting IP:

INFO[0001] SSH IP Address: 192.168.0.113