Editing CFEngine (section)

== Design ==

One of the main ideas in CFEngine is that changes in computer configuration should be carried out in a ''convergent'' manner.<ref name="a site configuration engine">{{cite journal |first=Mark |last=Burgess |authorlink=Mark Burgess (computer scientist) |title=Cfengine: a site configuration engine |journal=USENIX Computing Systems |location=Berkeley, CA, USA |publisher=[[USENIX]] |volume= 8 |issue=3 |date=Summer 1995 |url=https://www.usenix.org/legacy/publications/compsystems/1995/sum_burgess.pdf |accessdate=2014-08-22}}</ref><ref name="Configurable immunity">{{cite journal|first=Mark |last=Burgess |authorlink=Mark Burgess (computer scientist) |title=Configurable immunity for evolving human-computer systems |journal=Science of Computer Programming |volume=51 |issue=3 |date=2003-11-29 |pages=197–213 |doi=10.1016/j.scico.2003.12.004 |doi-access=free }}</ref> This means that each change operation made by the agent should have the character of a [[fixed point (mathematics)|fixed point]]. Rather than describing the steps needed to make a change, CFEngine language describes the final state in which one wants to end up. The agent then ensures that the necessary steps are taken to end up in this "policy compliant state". Thus, CFEngine can be run again and again, whatever the initial state of a system, and it will end up with a predictable result. CFEngine supports the item of statistical compliance with policy, meaning that a system can never guarantee to be exactly in an ideal or desired state, rather one approaches (converges) towards the desired state by best-effort, at a rate that is determined by the ratio of the frequency of environmental change to the rate of CFEngine execution.<ref name="On the theory of system administration">{{Cite journal |first=Mark |last=Burgess |authorlink=Mark Burgess (computer scientist) |title=On the theory of system administration |journal=Science of Computer Programming |volume=49 |year=2003 |issue=1–3 |pages=1–46 |doi=10.1016/j.scico.2003.08.001 |doi-access=free }}</ref>

CFEngine provides an operating system-independent interface to [[Unix-like]] host configuration. It requires some expert knowledge to deal with peculiarities of different operating systems, but has the power to perform maintenance actions across multiple hosts. CFEngine can be used on Windows hosts as well, and is widely used for managing large numbers of Unix hosts that run heterogeneous [[operating systems]], e.g. [[Solaris (operating system)|Solaris]], [[Linux]], [[AIX operating system|AIX]], [[Tru64 UNIX|Tru64]] and [[HP-UX]].{{cn|date=April 2023}}