Lightweight host for Linux system containers.
vpsAdminOS was designed for purposes of vpsFree.cz, a non-profit association that provides virtual servers to its members. We were using OpenVZ Legacy since 2009, but needed to upgrade to a newer kernel, as modern Linux distributions stopped supporting the OpenVZ Legacy kernel.
- LTS kernel with a mix of out-of-tree patches to improve container experience,
- runit as an init system,
- ZFS for storage,
- our own tools for system container management called osctl,
- LXC is used to run the containers,
- AppArmor for additional security,
- BIRD for network routing.
vpsAdminOS provides means to create and manage system containers, which look and feel as much as a virtual machine as possible. It focuses on user namespace and cgroup management to isolate the containers. All containers are running as unprivileged. One can set resource limits on a single container or groups of containers, allowing for fine-grained control and resource sharing.
osctl is an abstraction on top of LXC, managing system users, LXC homes, cgroups and system containers. vpsAdminOS uses ZFS to store containers and configuration.