Documentation/faq/releases.rst

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   6           http://www.apache.org/licenses/LICENSE-2.0
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   8       Unless required by applicable law or agreed to in writing, software
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  10       WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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  13
  14       Convention for heading levels in Open vSwitch documentation:
  15
  16       =======  Heading 0 (reserved for the title in a document)
  17       -------  Heading 1
  18       ~~~~~~~  Heading 2
  19       +++++++  Heading 3
  20       '''''''  Heading 4
  21
  22       Avoid deeper levels because they do not render well.
  23
  24 ========
  25 Releases
  26 ========
  27
  28 Q: What does it mean for an Open vSwitch release to be LTS (long-term support)?
  29
  30     A: All official releases have been through a comprehensive testing process
  31     and are suitable for production use.  Planned releases occur twice a year.
  32     If a significant bug is identified in an LTS release, we will provide an
  33     updated release that includes the fix.  Releases that are not LTS may not
  34     be fixed and may just be supplanted by the next major release.  The current
  35     LTS release is 2.5.x.
  36
  37     For more information on the Open vSwitch release process, refer to
  38     :doc:`/internals/release-process`.
  39
  40 Q: What Linux kernel versions does each Open vSwitch release work with?
  41
  42     A: The following table lists the Linux kernel versions against which the
  43     given versions of the Open vSwitch kernel module will successfully build.
  44     The Linux kernel versions are upstream kernel versions, so Linux kernels
  45     modified from the upstream sources may not build in some cases even if they
  46     are based on a supported version.  This is most notably true of Red Hat
  47     Enterprise Linux (RHEL) kernels, which are extensively modified from
  48     upstream.
  49
  50     ============ ==============
  51     Open vSwitch Linux kernel
  52     ============ ==============
  53     1.4.x        2.6.18 to 3.2
  54     1.5.x        2.6.18 to 3.2
  55     1.6.x        2.6.18 to 3.2
  56     1.7.x        2.6.18 to 3.3
  57     1.8.x        2.6.18 to 3.4
  58     1.9.x        2.6.18 to 3.8
  59     1.10.x       2.6.18 to 3.8
  60     1.11.x       2.6.18 to 3.8
  61     2.0.x        2.6.32 to 3.10
  62     2.1.x        2.6.32 to 3.11
  63     2.3.x        2.6.32 to 3.14
  64     2.4.x        2.6.32 to 4.0
  65     2.5.x        2.6.32 to 4.3
  66     2.6.x        3.10 to 4.7
  67     2.7.x        3.10 to 4.9
  68     2.8.x        3.10 to 4.12
  69     2.9.x        3.10 to 4.13
  70     2.10.x       3.10 to 4.17
  71     2.11.x       3.10 to 4.18
  72     ============ ==============
  73
  74     Open vSwitch userspace should also work with the Linux kernel module built
  75     into Linux 3.3 and later.
  76
  77     Open vSwitch userspace is not sensitive to the Linux kernel version.  It
  78     should build against almost any kernel, certainly against 2.6.32 and later.
  79
  80 Q: Are all features available with all datapaths?
  81
  82     A: Open vSwitch supports different datapaths on different platforms.  Each
  83     datapath has a different feature set: the following tables try to summarize
  84     the status.
  85
  86     Supported datapaths:
  87
  88     Linux upstream
  89       The datapath implemented by the kernel module shipped with Linux
  90       upstream.  Since features have been gradually introduced into the kernel,
  91       the table mentions the first Linux release whose OVS module supports the
  92       feature.
  93
  94     Linux OVS tree
  95       The datapath implemented by the Linux kernel module distributed with the
  96       OVS source tree.
  97
  98     Userspace
  99       Also known as DPDK, dpif-netdev or dummy datapath. It is the only
 100       datapath that works on NetBSD, FreeBSD and Mac OSX.
 101
 102     Hyper-V
 103       Also known as the Windows datapath.
 104
 105     The following table lists the datapath supported features from an Open
 106     vSwitch user's perspective.
 107
 108     ===================== ============== ============== ========= =======
 109     Feature               Linux upstream Linux OVS tree Userspace Hyper-V
 110     ===================== ============== ============== ========= =======
 111     NAT                   4.6            YES            Yes       NO
 112     Connection tracking   4.3            YES            PARTIAL   PARTIAL
 113     Tunnel - LISP         NO             YES            NO        NO
 114     Tunnel - STT          NO             YES            NO        YES
 115     Tunnel - GRE          3.11           YES            YES       YES
 116     Tunnel - VXLAN        3.12           YES            YES       YES
 117     Tunnel - Geneve       3.18           YES            YES       YES
 118     Tunnel - GRE-IPv6     4.18           YES            YES       NO
 119     Tunnel - VXLAN-IPv6   4.3            YES            YES       NO
 120     Tunnel - Geneve-IPv6  4.4            YES            YES       NO
 121     Tunnel - ERSPAN       4.18           YES            YES       NO
 122     Tunnel - ERSPAN-IPv6  4.18           YES            YES       NO
 123     QoS - Policing        YES            YES            YES       NO
 124     QoS - Shaping         YES            YES            NO        NO
 125     sFlow                 YES            YES            YES       NO
 126     IPFIX                 3.10           YES            YES       NO
 127     Set action            YES            YES            YES       PARTIAL
 128     NIC Bonding           YES            YES            YES       YES
 129     Multiple VTEPs        YES            YES            YES       YES
 130     Meters                4.15           YES            YES       NO
 131     Conntrack zone limit  4.18           YES            NO        NO
 132     ===================== ============== ============== ========= =======
 133
 134     Do note, however:
 135
 136     * Only a limited set of flow fields is modifiable via the set action by the
 137       Hyper-V datapath.
 138
 139     * Userspace datapath support, in some cases, is dependent on the associated
 140       interface types.  For example, DPDK interfaces support ingress and egress
 141       policing, but not shaping.
 142
 143     The following table lists features that do not *directly* impact an Open
 144     vSwitch user, e.g. because their absence can be hidden by the ofproto layer
 145     (usually this comes with a performance penalty).
 146
 147     ===================== ============== ============== ========= =======
 148     Feature               Linux upstream Linux OVS tree Userspace Hyper-V
 149     ===================== ============== ============== ========= =======
 150     SCTP flows            3.12           YES            YES       YES
 151     MPLS                  3.19           YES            YES       YES
 152     UFID                  4.0            YES            YES       NO
 153     Megaflows             3.12           YES            YES       NO
 154     Masked set action     4.0            YES            YES       NO
 155     Recirculation         3.19           YES            YES       YES
 156     TCP flags matching    3.13           YES            YES       NO
 157     Validate flow actions YES            YES            N/A       NO
 158     Multiple datapaths    YES            YES            YES       NO
 159     Tunnel TSO - STT      N/A            YES            NO        YES
 160     ===================== ============== ============== ========= =======
 161
 162 Q: What DPDK version does each Open vSwitch release work with?
 163
 164     A: The following table lists the DPDK version against which the given
 165     versions of Open vSwitch will successfully build.
 166
 167     ============ =======
 168     Open vSwitch DPDK
 169     ============ =======
 170     2.2.x        1.6
 171     2.3.x        1.6
 172     2.4.x        2.0
 173     2.5.x        2.2
 174     2.6.x        16.07.2
 175     2.7.x        16.11.8
 176     2.8.x        17.05.2
 177     2.9.x        17.11.4
 178     2.10.x       17.11.4
 179     ============ =======
 180
 181 Q: Are all the DPDK releases that OVS versions work with maintained?
 182
 183     No. DPDK follows YY.MM.n (Year.Month.Number) versioning.
 184
 185     Typically, all DPDK releases get a stable YY.MM.1 update with bugfixes 3
 186     months after the YY.MM.0 release. In some cases there may also be a
 187     YY.MM.2 release.
 188
 189     DPDK LTS releases start once a year at YY.11.0 and are maintained for
 190     two years, with YY.MM.n+1 releases around every 3 months.
 191
 192     The latest information about DPDK stable and LTS releases can be found
 193     at `DPDK stable`_.
 194
 195 .. _DPDK stable: http://dpdk.org/doc/guides/contributing/stable.html
 196
 197 Q: I get an error like this when I configure Open vSwitch:
 198
 199         configure: error: Linux kernel in <dir> is version <x>, but
 200         version newer than <y> is not supported (please refer to the
 201         FAQ for advice)
 202
 203     What should I do?
 204
 205     A: You have the following options:
 206
 207     - Use the Linux kernel module supplied with the kernel that you are using.
 208       (See also the following FAQ.)
 209
 210     - If there is a newer released version of Open vSwitch, consider building
 211       that one, because it may support the kernel that you are building
 212       against.  (To find out, consult the table in the previous FAQ.)
 213
 214     - The Open vSwitch "master" branch may support the kernel that you are
 215       using, so consider building the kernel module from "master".
 216
 217     All versions of Open vSwitch userspace are compatible with all versions of
 218     the Open vSwitch kernel module, so you do not have to use the kernel module
 219     from one source along with the userspace programs from the same source.
 220
 221 Q: What features are not available in the Open vSwitch kernel datapath that
 222 ships as part of the upstream Linux kernel?
 223
 224     A: The kernel module in upstream Linux does not include support for LISP.
 225     Work is in progress to add support for LISP to the upstream Linux version
 226     of the Open vSwitch kernel module. For now, if you need this feature, use
 227     the kernel module from the Open vSwitch distribution instead of the
 228     upstream Linux kernel module.
 229
 230     Certain features require kernel support to function or to have reasonable
 231     performance. If the ovs-vswitchd log file indicates that a feature is not
 232     supported, consider upgrading to a newer upstream Linux release or using
 233     the kernel module paired with the userspace distribution.
 234
 235 Q: Why do tunnels not work when using a kernel module other than the one
 236 packaged with Open vSwitch?
 237
 238     A: Support for tunnels was added to the upstream Linux kernel module after
 239     the rest of Open vSwitch. As a result, some kernels may contain support for
 240     Open vSwitch but not tunnels. The minimum kernel version that supports each
 241     tunnel protocol is:
 242
 243     ======== ============
 244     Protocol Linux Kernel
 245     ======== ============
 246     GRE      3.11
 247     VXLAN    3.12
 248     Geneve   3.18
 249     ERSPAN   4.18
 250     LISP     not upstream
 251     STT      not upstream
 252     ======== ============
 253
 254     If you are using a version of the kernel that is older than the one listed
 255     above, it is still possible to use that tunnel protocol. However, you must
 256     compile and install the kernel module included with the Open vSwitch
 257     distribution rather than the one on your machine. If problems persist after
 258     doing this, check to make sure that the module that is loaded is the one
 259     you expect.
 260
 261 Q: Why are UDP tunnel checksums not computed for VXLAN or Geneve?
 262
 263     A: Generating outer UDP checksums requires kernel support that was not part
 264     of the initial implementation of these protocols. If using the upstream
 265     Linux Open vSwitch module, you must use kernel 4.0 or newer. The
 266     out-of-tree modules from Open vSwitch release 2.4 and later support UDP
 267     checksums.
 268
 269 Q: What features are not available when using the userspace datapath?
 270
 271     A: Tunnel virtual ports are not supported, as described in the previous
 272     answer.  It is also not possible to use queue-related actions.  On Linux
 273     kernels before 2.6.39, maximum-sized VLAN packets may not be transmitted.
 274
 275 Q: Should userspace or kernel be upgraded first to minimize downtime?
 276
 277     A. In general, the Open vSwitch userspace should be used with the kernel
 278     version included in the same release or with the version from upstream
 279     Linux.  However, when upgrading between two releases of Open vSwitch it is
 280     best to migrate userspace first to reduce the possibility of
 281     incompatibilities.
 282
 283 Q: What happened to the bridge compatibility feature?
 284
 285     A: Bridge compatibility was a feature of Open vSwitch 1.9 and earlier.
 286     When it was enabled, Open vSwitch imitated the interface of the Linux
 287     kernel "bridge" module.  This allowed users to drop Open vSwitch into
 288     environments designed to use the Linux kernel bridge module without
 289     adapting the environment to use Open vSwitch.
 290
 291     Open vSwitch 1.10 and later do not support bridge compatibility.  The
 292     feature was dropped because version 1.10 adopted a new internal
 293     architecture that made bridge compatibility difficult to maintain.  Now
 294     that many environments use OVS directly, it would be rarely useful in any
 295     case.
 296
 297     To use bridge compatibility, install OVS 1.9 or earlier, including the
 298     accompanying kernel modules (both the main and bridge compatibility
 299     modules), following the instructions that come with the release.  Be sure
 300     to start the ovs-brcompatd daemon.