.. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. Convention for heading levels in Open vSwitch documentation: ======= Heading 0 (reserved for the title in a document) ------- Heading 1 ~~~~~~~ Heading 2 +++++++ Heading 3 ''''''' Heading 4 Avoid deeper levels because they do not render well. ======== Releases ======== Q: What does it mean for an Open vSwitch release to be LTS (long-term support)? A: All official releases have been through a comprehensive testing process and are suitable for production use. Planned releases occur twice a year. If a significant bug is identified in an LTS release, we will provide an updated release that includes the fix. Releases that are not LTS may not be fixed and may just be supplanted by the next major release. The current LTS release is 2.5.x. For more information on the Open vSwitch release process, refer to :doc:`/internals/release-process`. Q: What Linux kernel versions does each Open vSwitch release work with? A: The following table lists the Linux kernel versions against which the given versions of the Open vSwitch kernel module will successfully build. The Linux kernel versions are upstream kernel versions, so Linux kernels modified from the upstream sources may not build in some cases even if they are based on a supported version. This is most notably true of Red Hat Enterprise Linux (RHEL) kernels, which are extensively modified from upstream. ============ ============== Open vSwitch Linux kernel ============ ============== 1.4.x 2.6.18 to 3.2 1.5.x 2.6.18 to 3.2 1.6.x 2.6.18 to 3.2 1.7.x 2.6.18 to 3.3 1.8.x 2.6.18 to 3.4 1.9.x 2.6.18 to 3.8 1.10.x 2.6.18 to 3.8 1.11.x 2.6.18 to 3.8 2.0.x 2.6.32 to 3.10 2.1.x 2.6.32 to 3.11 2.3.x 2.6.32 to 3.14 2.4.x 2.6.32 to 4.0 2.5.x 2.6.32 to 4.3 2.6.x 3.10 to 4.7 2.7.x 3.10 to 4.9 2.8.x 3.10 to 4.12 2.9.x 3.10 to 4.13 2.10.x 3.10 to 4.17 2.11.x 3.10 to 4.18 2.12.x 3.10 to 5.0 2.14.x 3.10 to 5.5 ============ ============== Open vSwitch userspace should also work with the Linux kernel module built into Linux 3.3 and later. Open vSwitch userspace is not sensitive to the Linux kernel version. It should build against almost any kernel, certainly against 2.6.32 and later. Q: Are all features available with all datapaths? A: Open vSwitch supports different datapaths on different platforms. Each datapath has a different feature set: the following tables try to summarize the status. Supported datapaths: Linux upstream The datapath implemented by the kernel module shipped with Linux upstream. Since features have been gradually introduced into the kernel, the table mentions the first Linux release whose OVS module supports the feature. Linux OVS tree The datapath implemented by the Linux kernel module distributed with the OVS source tree. Userspace This datapath supports conventional system devices as well as DPDK and AF_XDP devices when support for those is built. This is the only datapath that works on NetBSD, FreeBSD and Mac OSX. Hyper-V Also known as the Windows datapath. The following table lists the datapath supported features from an Open vSwitch user's perspective. The "Linux upstream" column lists the Linux kernel version that introduced a given feature into its kernel module. The "Linux OVS tree" and "Userspace" columns list the Open vSwitch release versions that introduced a given feature into the included kernel module or the userspace datapath, respectively. ========================== ============== ============== ========= ======= Feature Linux upstream Linux OVS tree Userspace Hyper-V ========================== ============== ============== ========= ======= Connection tracking 4.3 2.5 2.6 YES Conntrack Fragment Reass. 4.3 2.6 2.12 YES Conntrack Timeout Policies 5.2 2.12 NO NO Conntrack Zone Limit 4.18 2.10 2.13 YES Conntrack NAT 4.6 2.6 2.8 YES Tunnel - LISP NO 2.11 NO NO Tunnel - STT NO 2.4 NO YES Tunnel - GRE 3.11 1.0 2.4 YES Tunnel - VXLAN 3.12 1.10 2.4 YES Tunnel - Geneve 3.18 2.4 2.4 YES Tunnel - GRE-IPv6 4.18 2.6 2.6 NO Tunnel - VXLAN-IPv6 4.3 2.6 2.6 NO Tunnel - Geneve-IPv6 4.4 2.6 2.6 NO Tunnel - ERSPAN 4.18 2.10 2.10 NO Tunnel - ERSPAN-IPv6 4.18 2.10 2.10 NO Tunnel - GTP-U NO NO 2.13 NO QoS - Policing YES 1.1 2.6 NO QoS - Shaping YES 1.1 NO NO sFlow YES 1.0 1.0 NO IPFIX 3.10 1.11 1.11 YES Set action YES 1.0 1.0 PARTIAL NIC Bonding YES 1.0 1.0 YES Multiple VTEPs YES 1.10 1.10 YES Meter action 4.15 2.10 2.7 NO ========================== ============== ============== ========= ======= Do note, however: * Only a limited set of flow fields is modifiable via the set action by the Hyper-V datapath. * Userspace datapath support, in some cases, is dependent on the associated interface types. For example, DPDK interfaces support ingress and egress policing, but not shaping. The following table lists features that do not *directly* impact an Open vSwitch user, e.g. because their absence can be hidden by the ofproto layer (usually this comes with a performance penalty). ===================== ============== ============== ========= ======= Feature Linux upstream Linux OVS tree Userspace Hyper-V ===================== ============== ============== ========= ======= SCTP flows 3.12 YES YES YES MPLS 3.19 YES YES YES UFID 4.0 YES YES NO Megaflows 3.12 YES YES NO Masked set action 4.0 YES YES NO Recirculation 3.19 YES YES YES TCP flags matching 3.13 YES YES NO Validate flow actions YES YES N/A NO Multiple datapaths YES YES YES NO Tunnel TSO - STT N/A YES NO YES ===================== ============== ============== ========= ======= Q: What DPDK version does each Open vSwitch release work with? A: The following table lists the DPDK version against which the given versions of Open vSwitch will successfully build. ============ ======= Open vSwitch DPDK ============ ======= 2.2.x 1.6 2.3.x 1.6 2.4.x 2.0 2.5.x 2.2 2.6.x 16.07.2 2.7.x 16.11.9 2.8.x 17.05.2 2.9.x 17.11.4 2.10.x 17.11.4 2.11.x 18.11.6 2.12.x 18.11.6 2.13.x 19.11.0 ============ ======= Q: Are all the DPDK releases that OVS versions work with maintained? No. DPDK follows YY.MM.n (Year.Month.Number) versioning. Typically, all DPDK releases get a stable YY.MM.1 update with bugfixes 3 months after the YY.MM.0 release. In some cases there may also be a YY.MM.2 release. DPDK LTS releases start once a year at YY.11.0 and are maintained for two years, with YY.MM.n+1 releases around every 3 months. The latest information about DPDK stable and LTS releases can be found at `DPDK stable`_. .. _DPDK stable: http://dpdk.org/doc/guides/contributing/stable.html Q: I get an error like this when I configure Open vSwitch: configure: error: Linux kernel in