It should build against almost any kernel, certainly against 2.6.32
and later.
-### Q: Are all features available with all versions of the kernel module?
-
-A: Features are gradually introduced into the upstream kernel so unless
- you are running the latest Linux release there may be some missing
- features. ovs-vswitchd probes for kernel features during startup and
- lists them in the ovs-vswitchd log file. If you need features that
- are unsupported, you can upgrade the Linux version or use the kernel
- module paired with the userspace distribution.
-
- For a given Open vSwitch release, the vast majority of features are
- supported when using the kernel module paired with the userspace
- distribution, no matter which kernel you build it against. However,
- from time to time, new features may be introduced which rely on
- functionality not available in older kernels. The features below are
- included in the kernel module distributed with OVS, but have more
- stringent requirements for minimum kernel versions than the support
- listed earlier.
-
-| Feature | Open vSwitch | Linux kernel
-|:---------:|:------------:|:------------:
-| STT | 2.4+ | 3.5+
-| Conntrack | 2.5+ | 3.10+
+### 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. Some features of
+ this module rely on functionality not available in older
+ kernels: in this case the minumum Linux version (against
+ which the feature can be compiled) is listed.
+
+ * *Userspace*: Also known as DPDK, dpif-netdev or dummy datapath. It is the
+ only datapath that works on NetBSD and FreeBSD.
+
+ * *Hyper-V*: Also known as the Windows datapath.
+
+ The following table lists the datapath supported features from
+ an Open vSwitch user's perspective.
+
+Feature | Linux upstream | Linux OVS tree | Userspace | Hyper-V |
+----------------------|:--------------:|:--------------:|:---------:|:-------:|
+Connection tracking | 4.3 | 3.10 | NO | NO |
+Tunnel - LISP | NO | YES | NO | NO |
+Tunnel - STT | NO | 3.5 | NO | YES |
+Tunnel - GRE | 3.11 | YES | YES | YES |
+Tunnel - VXLAN | 3.12 | YES | YES | YES |
+Tunnel - Geneve | 3.18 | YES | YES | NO |
+QoS - Policing | YES | YES | NO | NO |
+QoS - Shaping | YES | YES | NO | NO |
+sFlow | YES | YES | YES | NO |
+Set action | YES | YES | YES | PARTIAL |
+NIC Bonding | YES | YES | YES | NO |
+Multiple VTEPs | YES | YES | YES | NO |
+
+ **Notes:**
+ * Only a limited set of flow fields is modifiable via the set action by the
+ Hyper-V datapath.
+ * The Hyper-V datapath only supports one physical NIC per datapath. This is
+ why bonding is not supported.
+ * The Hyper-V datapath can have at most one IP address configured as a
+ tunnel endpoint.
+
+ 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 | NO |
+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 | NO |
+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: I get an error like this when I configure Open vSwitch: