[Mashiro]

Your quote of my reply "as is" in your above post is a bit out of context... anyway.

There is more information of the differences here: https://wiki.openvz.org/Comparison

^ However I don't necessarily think that the above information will help to properly identify the virt of your VPS. It could be OpenVZ 7 or a very similar but other virt technology. Fair enough I don't have enough experience to identify VZ7 due to lack of having owned or used a VZ 7 based VPS. Given the information about OpenVZ 6 you can however safely identify that your VPS might be NOT VZ 6.


Regarding the Docker control panel thing. I normally don't use control panels for a lot of things but for Docker if you really want to manage a lot of containers and etc. the only real control panel I can recommend is Portainer. It has everything you need or that you would also do based on CLI but with a GUI and everything integrated (docker hub, etc...).

[fitkoh]

Your quote of my reply "as is" in your above post is a bit out of context... anyway.

There is more information of the differences here: https://wiki.openvz.org/Comparison

^ However I don't necessarily think that the above information will help to properly identify the virt of your VPS. It could be OpenVZ 7 or a very similar but other virt technology. Fair enough I don't have enough experience to identify VZ7 due to lack of having owned or used a VZ 7 based VPS. Given the information about OpenVZ 6 you can however safely identify that your VPS might be NOT VZ 6.


Regarding the Docker control panel thing. I normally don't use control panels for a lot of things but for Docker if you really want to manage a lot of containers and etc. the only real control panel I can recommend is Portainer. It has everything you need or that you would also do based on CLI but with a GUI and everything integrated (docker hub, etc...).

I took a glance at the comparison chart, and you're right. I see a lot of unfamiliar terms and a lot of different types of virtualization with checkboxes in the same category, which would make identifying one or another somewhat difficult. I did notice when I ran virt-what I received 2 responses in the output: both openvz and lxc. I'm not sure if that's a clue or just more confusion to the puzzle.

I  have tried portainer. It's really neat! But I still need to play with it more in a sandbox and figure out exactly how to operate it. In my very limited experience I've had both success and failure with portainer. When it works, it works well. When it doesn't work, I don't have a clue why and retreat back to the command line. I have portainer installed but I usually leave it off so 1. less resource consumption and 2. less access points/better security.

[fChk]

And No!.. the problem is not Cgroups' support in your case, because CGroups are supported starting in Linux kernel 3.10; it's CGroups v2 that are implemented in kernel 4.15. And Docker engine requires CGroups v1 (v2 is still not supported by Docker last time I checked) for its process isolation for the containers it runs.

I had to comeback to this thread to correct and update the information conveyed in quote of mine.

I've said that 'CGroups are supported starting in Linux kernel 3.10' which is factually WRONG!.. As Control groups (cgroups v1) were merged into the Linux kernel since version 2.6.24, around 2007.

So where that kernel 3.10 come from?.. Well it's the absolute minimum kernel version that supports the features that Docker requires to run stable. Although, technically, you can still run Docker on a kernel 2.6.24 with a lot of hacks, exactly what OpenVZ was doing since then..

Same thing for CGroups v2 (aka unified hierarchy):
> CGroups v2 were first merged in kernel 4.5 but enabling cgroup v2 for containers required kernel 4.15 or later.

So basically my mind was focused on specific kernel versions pertaining to Docker support vis-a-vis of CGroups v1 and v2 while talking about CGroups in general in that quote. My mistake!

The other important update to add here is relative to this part of the quote:

(...) And Docker engine requires CGroups v1 (v2 is still not supported by Docker last time I checked) for its process isolation for the containers it runs.

As of Docker version 20.10 support of cgroup v2 and Rootless mode is now added.

Great news for Fedora users which switched to CGroups v2 by default since Fedora 31, released on October 29, 2019!

Since then it was imperative to resort to a hack to run Docker on that system which I've reluctantly done till I decided to migrate my Docker setup inside a KVM VM running CentOS 8 (actually the same VM that I've cloned from my old Phoenix VPS.)