Copy the files under /var/lib/docker is the easiest way to migrate docker to a new host. Before using this approach, this is some limitation.
- Operating system compatibility: The operating system on the new host must be compatible with the Docker images and containers you are migrating. For example, you cannot migrate containers built for a Linux environment to a Windows host.
- Container dependencies: If your containers have dependencies on specific hardware or software, these dependencies may not be met on the new host. You may need to modify your containers or install additional software to ensure they will work correctly.
- Network settings: If your containers are configured to use specific network settings, such as IP addresses or network ports, these settings may not be valid on the new host. You may need to modify your containers’ network settings to ensure they will work correctly.
- Docker version compatibility: As mentioned in the original statement, the target and source Docker versions should be the same. This is because Docker images and containers are specific to a certain version, and moving them between different versions may cause compatibility issues.
- Architecture compatibility: As also mentioned in the original statement, the target and source architectures of the host should be the same. For example, you cannot move containers built for an x86 architecture to a host with an ARM architecture.
- Container state: If the container’s state is changing frequently, e.g. lots of new files or changes inside the container while you are copying the files, the copied container may not reflect the current state of the original container.