Content deleted Content added
→Flexibility: Add URL in reference |
No edit summary |
||
| (One intermediate revision by one other user not shown) | |||
Line 2:
{{More citations needed|date=November 2020}}
'''OS-level virtualization''' is an [[operating system]] (OS) [[virtualization]] paradigm in which the [[Kernel (operating system)|kernel]] allows the existence of multiple isolated [[user space and kernel space|user space]] instances, including '''containers''' ([[LXC]], [[Solaris Containers]], AIX [[Workload_Partitions|WPARs]], HP-UX SRP Containers, [[Docker (software)|Docker]], [[Podman]], [[Guix]]), '''zones''' ([[Solaris Containers]]), '''virtual private servers''' ([[OpenVZ]]), '''partitions''', '''virtual environments''' ('''VEs'''), '''virtual kernels''' ([[vkernel|DragonFly BSD]]), and '''jails''' ([[FreeBSD jail]] and [[chroot]]).<ref>{{Cite web |url=https://www.networkworld.com/article/749098/cisco-subnet-software-containers-used-more-frequently-than-most-realize.html |title=Software containers: Used more frequently than most realize |last1=Hogg |first1=Scott |date=2014-05-26 |website=[[Network World]] |publisher=Network world, Inc. |access-date=2015-07-09 |quote=There are many other OS-level virtualization systems such as: Linux OpenVZ, Linux-VServer, FreeBSD Jails, AIX Workload Partitions (WPARs), HP-UX Containers (SRP), Solaris Containers, among others. }}</ref> Such instances may look like real computers from the point of view of programs running in them. A [[computer program]] running on an ordinary operating system can see all resources (connected devices, files and folders, [[Shared resource|network shares]], CPU power, quantifiable hardware capabilities) of that computer. Programs running inside a [[Containerization (computing)|container]] can only see the container's contents and devices assigned to the container.
On [[Unix-like]] operating systems, this feature can be seen as an advanced implementation of the standard [[chroot]] mechanism, which changes the apparent root folder for the current running process and its children. In addition to isolation mechanisms, the kernel often provides [[Resource management (computing)|resource-management]] features to limit the impact of one container's activities on other containers. Linux containers are all based on the virtualization, isolation, and resource management mechanisms provided by the [[Linux kernel]], notably [[Linux namespaces]] and [[cgroups]].<ref>{{cite web|url=http://www.netdevconf.org/1.1/proceedings/slides/rosen-namespaces-cgroups-lxc.pdf|title=Namespaces and Cgroups, the basis of Linux Containers|first=Rosen|last=Rami|access-date=18 August 2016}}</ref>
Line 363:
* [https://www.kernelthread.com/publications/virtualization/ An introduction to virtualization] {{Webarchive|url=https://web.archive.org/web/20191128152118/http://www.kernelthread.com/publications/virtualization |date=2019-11-28 }}
* [https://wiki.openvz.org/Introduction_to_virtualization A short intro to three different virtualization techniques]
* [https://thijs.ai/papers/scheepers-virtualization-containerization.pdf Virtualization and containerization of application infrastructure: A comparison] {{Webarchive|url=https://web.archive.org/web/20230315103310/https://thijs.ai/papers/scheepers-virtualization-containerization.pdf |date=2023-03-15 }}, June 22, 2015, by Mathijs Jeroen Scheepers
* [https://lwn.net/Articles/646054/ Containers and persistent data], [[LWN.net]], May 28, 2015, by Josh Berkus
| |||