FreeBSD Jails


The FreeBSD jail mechanism is an implementation of operating system-level virtualization that allows administrators to partition a FreeBSD-based computer system into several independent mini-systems called jails.

The need for the FreeBSD jails came from service providers' desire to establish a clean, clear-cut separation between their services and their customers, mainly for security and ease of administration. Instead of adding a new layer of fine-grained configuration options, the solution adopted was to compartmentalize the system, both its files and its resources, in such a way that only the right person(s) are allowed access to the right compartment(s).


  1. CSE does not presently host any FreeBSD jails.
  2. Because jails are virtual services that share system CPU and memory with the other services hosted on the physical machine, use jails on services that are not expected to have much overhead and are not expected to grow very much.


  2. % man jails