Open vSwitch

Last updated

Open vSwitch
Open vSwitch Logo.svg
Initial releaseJuly 29, 2009;10 years ago (2009-07-29) [1]
Stable release
2.12.0 [2] / September 10, 2019;8 months ago (2019-09-10)
Repository OOjs UI icon edit-ltr-progressive.svg
Written in C
Operating system Linux, Hyper-V, FreeBSD and NetBSD
Type Virtual network switch
License Apache License 2.0

Open vSwitch, sometimes abbreviated as OVS, is an open-source implementation of a distributed virtual multilayer switch. The main purpose of Open vSwitch is to provide a switching stack for hardware virtualization environments, while supporting multiple protocols and standards used in computer networks. [3]


The project's source code is distributed under the terms of Apache License 2.0.


Open vSwitch deployed as a cross-server virtual network switch, transparently distributed across multiple physical servers. Distributed Open vSwitch instance.svg
Open vSwitch deployed as a cross-server virtual network switch, transparently distributed across multiple physical servers.

Open vSwitch is a software implementation of a virtual multilayer network switch, designed to enable effective network automation through programmatic extensions, while supporting standard management interfaces and protocols such as NetFlow, sFlow, SPAN, RSPAN, CLI, LACP and 802.1ag. In addition, Open vSwitch is designed to support transparent distribution across multiple physical servers by enabling creation of cross-server switches in a way that abstracts out the underlying server architecture, similar to the VMware vNetwork distributed vswitch or Cisco Nexus 1000V. [4] [5] [6]

Open vSwitch can operate both as a software-based network switch running within a virtual machine (VM) hypervisor, and as the control stack for dedicated switching hardware; as a result, it has been ported to multiple virtualization platforms, switching chipsets, and networking hardware accelerators. [7] Open vSwitch is the default network switch in the XenServer virtualization platform since its version 6.0, [8] and in the Xen Cloud Platform via its XAPI management toolstack. [9] It also supports Xen, Linux KVM, Proxmox VE and VirtualBox hypervisors, while a port to Hyper-V is also available. [10] Open vSwitch has also been integrated into various cloud computing software platforms and virtualization management systems, including OpenStack, openQRM, OpenNebula and oVirt. [4] [5]

The Linux kernel implementation of Open vSwitch was merged into the kernel mainline in kernel version 3.3, which was released on March 18, 2012; [11] [12] official Linux packages are available for Debian, Fedora, openSUSE and Ubuntu. [4] As of January 2014, FreeBSD and NetBSD implementations are also available, with the NetBSD's implementation operating completely in userspace. [13] [14] [15]

The majority of the Open vSwitch source code is written in platform-independent C language, which provides easy portability to various environments. The source code is licensed under the Apache License 2.0. [4]


As of September 2015, features provided by Open vSwitch include the following: [16] [17]

See also

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  1. "A complete list of Open vSwitch releases". Archived from the original on November 9, 2017. Retrieved April 2, 2014.
  2. Justin Pettit (September 10, 2019). "[ovs-announce] Open vSwitch 2.12.0 Available". Retrieved September 10, 2019.
  3. 1 2 M. Tim Jones (October 27, 2010). "Virtual networking in Linux". IBM . Retrieved April 9, 2014.
  4. 1 2 3 4 "Open vSwitch: An Open Virtual Switch". Retrieved November 24, 2013.
  5. 1 2 Thomas Graf (April 24, 2013). "Underneath OpenStack Quantum: Software Defined Networking with Open vSwitch" (PDF). Red Hat . Retrieved April 9, 2014.
  6. Ralf Spenneberg. "Virtual switching with Open vSwitch". Retrieved April 2, 2014.
  7. "Tilera Launches Open Virtual Switch Solution (OVS) to Accelerate NFV and SDN". Marketwired. February 24, 2014. Retrieved June 22, 2015.
  8. "XenServer 6.0 Release Notes". Citrix Systems. March 8, 2012. Retrieved January 22, 2015.
  9. "XAPI: Open source software to build private and public clouds". 2013. Retrieved January 22, 2015.
  10. Alessandro Pilotti (May 22, 2014). "Open vSwitch on Hyper-V". Retrieved June 22, 2015.
  11. "Linux kernel 3.3, Section 1.3. Open vSwitch". March 18, 2012. Retrieved April 2, 2014.
  12. Jonathan Corbet (November 30, 2011). "Routing Open vSwitch into the mainline". . Retrieved April 2, 2014.
  13. "FreshPorts – net/openvswitch". December 30, 2013. Retrieved April 2, 2014.
  14. Gaetano Catalli (November 7, 2011). "Open vSwitch: performance improvement and porting to FreeBSD" (PDF). Retrieved June 22, 2015.
  15. "openvswitch/ovs: ovs/INSTALL.NetBSD at master". January 11, 2014. Archived from the original on April 9, 2014. Retrieved April 9, 2014.
  16. "Open vSwitch: Features". Retrieved September 17, 2015.
  17. Jesse Gross (September 2013). "Programmable Networking with Open vSwitch" (PDF). LinuxCon . Retrieved November 24, 2013.
  18. Justin Pettit; Ben Pfaff; Ethan Jackson (November 13, 2014). "Accelerating Open vSwitch to 'Ludicrous Speed'". Retrieved May 26, 2015.
  19. Jesse Gross (August 21, 2014). "The Evolution of Open vSwitch" (PDF). LinuxCon. pp. 6, 13–17. Retrieved May 28, 2015.