Docker on XCP-ng

[dan2462]

@olivierlambert

[olivierlambert]

What do you mean by "natively"?

[jefftee]

I run an Ubuntu 20.04 LTS virtual machine that has all of my docker containers running... One of the containers is Portainer, which provides a nice web gui to manage the docker containers.

I see @olivierlambert mentioned a plug-in that makes the containers visible to XO. I wasn't aware such a thing exists, but I'm going to go google it now and see if I can get that working...

[jmccoy555]

@jefftee https://github.com/xcp-ng/xcp/wiki/Docker-in-XCP-ng

[kevdog]

@jmccoy555

I tried the method you linked to with github. I was excited at first when I saw the containers tab in the UI. Later I created a number of docker containers and such within the VM. I came back later to the XO UI and saw none of the new containers. This feature seems a little bit borked to me.

[olivierlambert]

You should have a Docker tab displayed, if not, the plugin isn't correctly installed.

[kevdog]

All I have is a container tab. I tried to upload a jpeg screenshot but for some reason your forums isn't taking it and I'm getting a lot of pop up errors trying to insert the image. I followed the instructions linked by @jmccoy above. I already had an existing VM. Do you have any additional instructions?

By the way -- the error on the image upload was the following:

Something went wrong installing the "sharp" module /lib64/libz.so.1: version `ZLIB_1.2.9' not found (required by /usr/share/nginx/html/forum/node_modules/sharp/build/Release/../../vendor/lib/libpng16.so.16) - Remove the "node_modules/sharp" directory then run "npm install --ignore-scripts=false --verbose" and look for errors - Consult the installation documentation at https://sharp.pixelplumbing.com/install - Search for this error at https://github.com/lovell/sharp/issues

[kevdog]

Here is my screenshot:

The listed containers don't exist on the host anymore.

[olivierlambert]

XO is just getting the output of the Docker plugin installed on the host. You can check that by doing the call with xe.

So the problem is more likely to be inside the plugin or the connection with the OS itself.

[ganeshb]

If XCP-NG doesn't support Docker, can you tell me which kernel supports Docker.

[olivierlambert]

This sentence doesn't make sense. You can run Docker in any VM on top of Xen.

[ganeshb]

@olivierlambert @olivierlambert I want to install docker on XCP-ng. Not on the VM on top of XCP. Is there any solution to do so??? Please suggest

[ravenet]

@ganeshb
https://xcp-ng.org/blog/2021/09/14/runx-next-generation-secured-containers/

[olivierlambert]

@ganeshb This is NOT a good idea. In fact, that's a very bad idea for a lot of reasons.

Dom0 is already a VM, so installing Docker in there or in a "normal" guest is the same thing, except that's a bad security thing to install it inside a privileged environment.

[olivierlambert]

A reminder:

There's no host, everything is a VM.

[vsaad]

@ganeshb Hi, think twice before going this path, with the xcp and the ubuntu hosting the containers seems to be a very good solution.
You can make good use of xcp features as backups snapshots, if something goes wrong, you can easily restore everything. You shouldn't be accessing dom0 if you aren't 100% sure of what u doing.

I havent used in prod but the coreos + the plugin looks the most native xen docker compatibility since xenserver 7.0 (I think), which would be more towards enterprises solutions.
CoreOS is RedHat based and a bit different than Debian based.

Between Large and small prod environments I'd say you are going fine.
If you want just for a home/small lab, you can try freenas which already comes with a web dashboard.

I hope it helps