I tried to run Docker on a virtual machine.
Host : MacBook
VM : Parallels Windows 7
And error occurs:
Is it possible?
If the VM is a Linux, you can do this without any problem - on Linux, the Docker is essentially a well-worked chroot. Thus, the Linux docker is not virtualization.
In the case of Windows, it is not so easy. Windows Docker internally uses Hyper-V to emulate the containers. Which means that you can only run, if you can use nested virtualization:
On your host machine runs a Windows VM
Inside your Windows VM, runs a HyperV
HyperV is managed by the docker installed on your virtual Windows.
I tried qemu/kvm, virtualbox and vmware player. I configured them deeply and strongly, I've hacked them, I did every possible to do. Only the last worked (VMWare).
There are significant speed costs, but it may be useful for development on Linux, and then trial-test on Windows configurations.
You will need a lot of ram. At least 16G. 32G is better. A relative useful configuration would be:
32GB physical RAM for the physical host
12GB virtual RAM for the Windows VM running on it
8GB virtual RAM inside the Windows VM for the HyperV Linux host.
Sometimes it will be a little bit buggy, but only your HyperV will crash out, your virtual Win, or your host machine won't. It is okay for testing a docker container on a Windows machine, what you've developed on a Linux. Don't create mission critical servers on this way. :-)
You're using Docker Machine in your Windows VM, which is actually going to create a Linux VM inside the Windows VM on your Mac. You can do that, but you need to enable nested virtualization - which I'm not sure you can do in Parallels 7.
Instead you can run Docker Machine on the Mac directly and use Parallels to create the Linux VM - which means Docker is running in a Linux VM on your Mac, and you don't need nested virtualization.
Or preferably use Docker for Mac if your OS supports it, it's the latest product and has much better host integration than Docker Machine.
If you would be using Windows 10/11 Pro or Enterprise and Hyper-V, then all you must do is to enable nested virtualization. On your host, just run (with your guest off):
> Set-VMProcessor -VMName <VMName> -ExposeVirtualizationExtensions $true
Now you can start your guest and run Docker Desktop as normal.
According to Docker's terms I don't think it's allowed. Section 4.1(b)(vii) says you shall not "use the Service on virtual machines." For clarification, "'Service' refers to the applications, software (including any Open Source Software), products and services provided by Docker, including any beta or trial versions."
If I am reading this right, that means it's illegal to run Docker on any VM.
Worked perfectly fine. Base OS win 10 pro with VirtualBox Version: 6.1 and vagrant with ubuntu 20.04. Using vagrant box follow docker instructions. With vagrant public network no need for port forwarding all apps were accessible.
Previous persons comment is very concerning considering on Windows and Mac you run docker inside a virtual machine lul. Windows uses WSL2 and Mac uses an arm linux machine to manage its docker.
Also, you can run docker in a vm, but it must be linuxOS vm as windows 7 does not support docker.
Related
My production instance is running under Ubuntu 16 while my local machine runs under Windows 10.
In order to have a setup close to my production, I use VMs (vagrant, virtualbox, homestead). Btw, my application is a Laravel app so homestead is the route to go as per its documentation.
Since I have multiple applications that have different specifications (different OS version, different app versions), I need to set multiple VMs as well. Since VMs are resource-heavy, it tends to slow down my machine in time.
That then, I came across Docker. Will Docker for Windows and create containers and images base on my app's specification suffice or do I still need a VM then create docker containers from there?
Below is a diagram
Windows running Docker for Windows
Windows running Ubuntu VM with Docker
Docker-Desktop will by default start and run a Linux VM in the background of your Windows System.
https://docs.docker.com/docker-for-windows/install/
Hyper-V and Containers Windows features must be enabled.
You can also use WLS/2 which is basically the same thing.
https://docs.docker.com/docker-for-windows/wsl/
Jens
From what I understand, the container includes all dependencies to run, but all containers running on the same platform whether it's a VM, or bare-metal will share the underlying kernel.
I believe I read somewhere that in order to run linux containers on windows, the Docker client spins up a linux based VM, and runs the container in that.
But now I see that docker for windows runs linux containers natively (ie, without hyper-v).
My question is: How can an image that was built to run on linux run on a system that has a windows kernel?
This is the original source that my question arose from:
https://www.hanselman.com/blog/DockerAndLinuxContainersOnWindowsWithOrWithoutHyperVVirtualMachines.aspx
With the latest version of Windows 10 (or 10 Server) and the beta of
Docker for Windows, there's native Linux Container support on Windows.
That means there's no Virtual Machine or Hyper-V involved (unless you
want), so Linux Containers run on Windows itself using Windows 10's
built in container support.
I saw some similar questions, but they explained how a linux container runs on a windows platform by utilising a vm/hyper-v
How docker desktop runs linux containers on Windows machine
Does "Docker On Windows" launch a linux virtual machine?
Perhaps I didn't understand their answers, but from what I understood, it still seems like the linux container is sitting on-top of the windows kernel.
this is the magic of LCOW (https://github.com/linuxkit/lcow)
you are right to run a container the base KERNEL should be same , since container is just an abstraction , so to run a linux container on windows there are two options
either use moby linux on hyperv and run containers there
use lcow to run light weight linux vm for each container. (lcow)
https://learn.microsoft.com/en-us/virtualization/windowscontainers/deploy-containers/linux-containers
with WSL in windows in future we might be able to get a third method don't know if already someone is working on it .
Does Docker require Hyper-V enabled in windows? If yes, why?
What is the role of Hyper-V in this case?
I m using Windows 10 home. What is the alternative for hyper-V to install Docker pls?
If you use windows10 professional & your bios supports hardware virtualization, suggest you to enable Hyper-V.
When run linux container in windows10, in fact, it still needs a linux system as a docker host, because linux container cannot share kernel with windows.
If enable hyper-v, docker-windows will auto setup a MobyLinuxVm in hyper-v as a virtual machine which act as the host machine of docker. Compared to traditional solution, I mean install a linux in virtualbox. Hyper-v has much better performance, because it does not depend on windows os, it something like setup based on hardware just like vmware-esx.
Finally, if you use home version of windows10, you had to install a virtualbox as the host machine of docker and use docker toolbox, details refers to https://docs.docker.com/toolbox/overview/ for legacy desktop solution.
Update some additional points you may want to know:
a) linux container:
Docker container had to share kernel with host, there are no linux kernel on windows, so for all situations, you had to have a virtual machine with linux as docker host, either hyper-v or virtualbox if no hyper-v support.
b) windows container:
In theory, windows container could share the kernel of windows, so no virtual machine needed.
But microsoft support container too late compared to linux, so for different host, it use different solutions, see next chapter from microsoft web site:
Windows Containers include two different container types, or runtimes.
Windows Server Containers – provide application isolation through process and namespace isolation technology. A Windows Server Container shares a kernel with the container host and all containers running on the host. These containers do not provide a hostile security boundary and should not be used to isolate untrusted code. Because of the shared kernel space, these containers require the same kernel version and configuration.
Hyper-V Isolation – expands on the isolation provided by Windows Server Containers by running each container in a highly optimized virtual machine. In this configuration, the kernel of the container host is not shared with other containers on the same host. These containers are designed for hostile multitenant hosting with the same security assurances of a virtual machine. Since these containers do not share the kernel with the host or other containers on the host, they can run kernels with different versions and configurations (with in supported versions) - for example all Windows containers on Windows 10 use Hyper-V isolation to utilize the Windows Server kernel version and configuration.
There is a github project VRouter which make Openwrt image as an vbox on macOS and routing the traffic to the NIC of the virtual machine as a transparent proxy. I would like to know that is it possible to do these things o with docker?
As fas as I know, docker for mac actually run inside a virtual machine on mac and there is no docker0 NIC on macOS. I found a project tuntaposx and a tuntap support shim installer for Docker for Mac docker-tuntap-osx which make it access docker container inside the virtual machine from macOS instead of publish ports possible. But What's the next step? I am quite confused about network issue. Can someone give me a hint about it?
Docker requires a Linux host to run. It's unlikely it will ever directly support MacOS, or Windows, without some kind of VM running.
Docker isn't a virtual machine. It uses various features of the Linux kernel to essentially simulate a virtual server, but it isn't actually doing full virtualization.
I'm aware that the old Docker Toolbox uses VirtualBox to run a minimal linux virtual machine for Docker using boot2docker which is a minimal light-weight Linux OS. Now, with the new Docker on Windows they claim that they use HyperVisor on Windows 10 Pro directly.
Does this mean the Docker on Windows package got rid of the Linux virtual machine totally, or is there still a Linux virtual machine being used on Windows?
A container is considered “native”, if it can run directly on the host operating system.
Linux Container - A Linux application that runs in an isolated Linux environment.
This same container can be run on a Windows OS using virtualization to emulate a Linux environment, but the container is still running on Linux.
Windows (Server) Container - A Windows application that runs in an isolated Windows environment.
Docker on Windows to run a Linux container requires virtualization. The available options are:
VirtualBox (Docker Toolbox)
Hyper-V backend (Docker Desktop)
WSL2 backend (Docker Desktop)
The Container (and Docker) terminology is very confusing, especially with Windows nuances. See Docker Container in Linux and Windows for an overview with many useful reference links.