I experimented with LXD containers on Linux recently, but I found the technology it builds on (cgroups) too hard to wrap my head around, and tutorials leave me in the dark. E.g. here is page 2 of one tutorial: https://access.redhat.com/documentation/en-us/red_hat_enterp... All these rules made no sense to me, and while I suppose they become clear at some point, I like my tutorials to be clear from the start.
That's documentation for RHEL 6 which is now 12 years old. It pertains to cgroups v1 which was horribly complex. It was replaced by cgroups v2 which is much simpler; there's now a single hierarchy of cgroups. https://access.redhat.com/documentation/en-us/red_hat_enterp... That said I don't remember having to learn all that much about cgroups when I last looked at lxc...
Well, I started looking into it because there were all these mounted filesystems that I couldn't unmount, even as root. I guess I will have to look into namespaces also.