How to configure LXC containers (_NOT LXD_) on fly?

For ex. mount inside something or change/add static Ip address, increase RAM, etc., without restart container?

lxc config && using profiles to define what you need (prehaps cloud-init look at the user.user-data keys)

Are u confuse lxc and lxd? The question is about LXC, not LXD.

lxc-cgroup can do live cgroup updates.

The rest you’d need to do from the C API or using custom scripts.

Yeah, i can change RAM with lxc-cgroup , but what about mount something or change IP? Did I understand correctly, there is no any command (for ex.: lxc-mount or lxc-net) to do that?

That’s correct, there is no such commands and in many cases, no C API for that either.

And that’s sad too, but thaks a lot, @stgraber !