Q: What is Open vSwitch?
Open vSwitch is a production quality open source software switch designed to be used as a vswitch in virtualized server environments. A vswitch forwards traffic between different VMs on the same physical host and also forwards traffic between VMs and the physical network. Open vSwitch supports standard management interfaces (e.g. sFlow, NetFlow, RSPAN, CLI), and is open to programmatic extension and control using OpenFlow and the OVSDB management protocol.
Open vSwitch as designed to be compatible with modern switching chipsets. This means that it can be ported to existing high-fanout switches allowing the same flexible control of the physical infrastructure as the virtual infrastructure. It also means that Open vSwitch will be able to take advantage of on-NIC switching chipsets as their functionality matures.
Q: What virtualization platforms can use Open vSwitch?
Open vSwitch can currently run on any Linux-based virtualization platform (kernel 2.6.18 and newer), including: KVM, VirtualBox, Xen, Xen Cloud Platform, XenServer. The bulk of the code is written in platform-independent C and is easily ported to other environments. We welcome inquires about integrating Open vSwitch with other virtualization platforms.
Q: How can I try Open vSwitch?
Open vSwitch is as source code to be built on a Linux system. You can build and experiment with Open vSwitch on any Linux machine. Packages for various Linux distributions are underway and will be linked to from this website as they materialize.
You may also download and run a virtualization platform that already has Open vSwitch integrated. For example, download the ISO for Xen Cloud Platform. Be aware that the version integrated with a particular platform may not be the most recent Open vSwitch release.
Q: Why would I use Open vSwitch instead of the Linux bridge?
Open vSwitch is specially designed to make it easier to manage VM network configuration and monitoring state spread across many physical hosts in dynamic virtualized environments. Please see WHY OVS for a more detailed description of how Open vSwitch relates to the Linux Bridge.
Q: How is Open vSwitch related to distributed virtual switches like the VMware vNetwork distributed switch or the Cisco Nexus 1000V?
Distributed vswitch applications (e.g., VMware vNetwork distributed switch, Cisco Nexus 1000V) provide a centralized way to configure and monitor the network state of VMs that are spread across many physical hosts. Open vSwitch is not a distributed vswitch itself, rather it runs on each physical host and supports remote management in a way that makes it easier for developers of virtualization/cloud management platforms to offer distributed vswitch capabilities.
To aid in distribution, Open vSwitch provides two open protocols that are specially designed for remote management in virtualized network environments: OpenFlow, which exposes flow-based forwarding state, and the OVSDB management protocol, which exposes switch port state. In addition to the switch implementation itself, Open vSwitch includes tools (ovs-controller, ovs-ofctl, ovs-vsctl) that developers can script and extend to provide distributed vswitch capabilities that are closely integrated with their virtualization management platform.
Q: Why doesn’t Open vSwitch support distribution? Open vSwitch is intended to be a useful component for building flexible network infrastructure. There are many different approaches to distribution which balance trade-offs between simplicity, scalability, hardware compatibility, convergence times, logical forwarding model, etc. The goal of Open vSwitch is to be able to support all as a primitive building block rather than choose a particular point in the distributed design space.
Q: What does it mean for an Open vSwitch release to be “stable”?
A stable Open vSwitch release is code that has been through a comprehensive testing process and is suitable for production use. Planned stable releases will occur several times a year. If a significant bug is identified in a stable release, we will provide an updated stable release that includes the fix. Developers looking to test the latest Open vSwitch code can use an “unstable” release or directly access the code via git.
Q: How can I contribute to the Open vSwitch Community?
You can start by joining the mailing lists and helping to answer questions.
You can also suggest improvements to documentation or offer to write a configuration cookbook entry.
If you have a feature or bug you would like to work on send a mail to dev mailing list.