How to import physical or virtual machines to LXD instances#

LXD provides a tool (lxd-migrate) to create a LXD instance based on an existing disk or image.

You can run the tool on any Linux machine. It connects to a LXD server and creates a blank instance, which you can configure during or after the migration. The tool then copies the data from the disk or image that you provide to the instance.

The tool can create both containers and virtual machines:

  • When creating a container, you must provide a disk or partition that contains the root file system for the container. For example, this could be the / root disk of the machine or container where you are running the tool.

  • When creating a virtual machine, you must provide a bootable disk, partition or image. This means that just providing a file system is not sufficient, and you cannot create a virtual machine from a container that you are running. It is also not possible to create a virtual machine from the physical machine that you are using to do the migration, because the migration tool would be using the disk that it is copying. Instead, you could provide a bootable image, or a bootable partition or disk that is currently not in use.

Complete the following steps to migrate an existing machine to a LXD instance:

  1. Download the bin.linux.lxd-migrate tool from the Assets section of the latest LXD release.

  2. Place the tool on the machine that you want to use to create the instance. Make it executable (usually by running chmod u+x bin.linux.lxd-migrate).

  3. Make sure that the machine has rsync installed. If it is missing, install it (for example, with sudo apt install rsync).

  4. Run the tool:

    ./bin.linux.lxd-migrate
    

    The tool then asks you to provide the information required for the migration.

    Tip

    As an alternative to running the tool interactively, you can provide the configuration as parameters to the command. See ./bin.linux.lxd-migrate --help for more information.

    1. Specify the LXD server URL, either as an IP address or as a DNS name.

    2. Check and confirm the certificate fingerprint.

    3. Choose a method for authentication (see Remote API authentication).

      For example, if you choose using a certificate token, log on to the LXD server and create a token for the machine on which you are running the migration tool with lxc config trust add. Then use the generated token to authenticate the tool.

    4. Choose whether to create a container or a virtual machine.

    5. Specify a name for the instance that you are creating.

    6. Provide the path to a root file system (for containers) or a bootable disk, partition or image file (for virtual machines).

    7. For containers, optionally add additional file system mounts.

    8. For virtual machines, specify whether secure boot is supported.

    9. Optionally, configure the new instance. You can do so by specifying profiles, directly setting configuration options or changing storage or network settings.

      Alternatively, you can configure the new instance after the migration.

    10. When you are done with the configuration, start the migration process.

    Expand to see an example output
    Please provide LXD server URL: https://192.0.2.7:8443
    Certificate fingerprint: xxxxxxxxxxxxxxxxx
    ok (y/n)? y
    
    1) Use a certificate token
    2) Use an existing TLS authentication certificate
    3) Generate a temporary TLS authentication certificate
    Please pick an authentication mechanism above: 1
    Please provide the certificate token: xxxxxxxxxxxxxxxx
    
    Remote LXD server:
      Hostname: bar
      Version: 5.4
    
    Would you like to create a container (1) or virtual-machine (2)?: 1
    Name of the new instance: foo
    Please provide the path to a root filesystem: /
    Do you want to add additional filesystem mounts? [default=no]:
    
    Instance to be created:
      Name: foo
      Project: default
      Type: container
      Source: /
    
    Additional overrides can be applied at this stage:
    1) Begin the migration with the above configuration
    2) Override profile list
    3) Set additional configuration options
    4) Change instance storage pool or volume size
    5) Change instance network
    
    Please pick one of the options above [default=1]: 3
    Please specify config keys and values (key=value ...): limits.cpu=2
    
    Instance to be created:
      Name: foo
      Project: default
      Type: container
      Source: /
      Config:
        limits.cpu: "2"
    
    Additional overrides can be applied at this stage:
    1) Begin the migration with the above configuration
    2) Override profile list
    3) Set additional configuration options
    4) Change instance storage pool or volume size
    5) Change instance network
    
    Please pick one of the options above [default=1]: 4
    Please provide the storage pool to use: default
    Do you want to change the storage size? [default=no]: yes
    Please specify the storage size: 20GiB
    
    Instance to be created:
      Name: foo
      Project: default
      Type: container
      Source: /
      Storage pool: default
      Storage pool size: 20GiB
      Config:
        limits.cpu: "2"
    
    Additional overrides can be applied at this stage:
    1) Begin the migration with the above configuration
    2) Override profile list
    3) Set additional configuration options
    4) Change instance storage pool or volume size
    5) Change instance network
    
    Please pick one of the options above [default=1]: 5
    Please specify the network to use for the instance: lxdbr0
    
    Instance to be created:
      Name: foo
      Project: default
      Type: container
      Source: /
      Storage pool: default
      Storage pool size: 20GiB
      Network name: lxdbr0
      Config:
        limits.cpu: "2"
    
    Additional overrides can be applied at this stage:
    1) Begin the migration with the above configuration
    2) Override profile list
    3) Set additional configuration options
    4) Change instance storage pool or volume size
    5) Change instance network
    
    Please pick one of the options above [default=1]: 1
    Instance foo successfully created