<dt><code>tap</code></dt>
<dd>A TUN/TAP device managed by Open vSwitch.</dd>
<dt><code>gre</code></dt>
- <dd>An Ethernet over RFC 1702 Generic Routing Encapsulation over IPv4
+ <dd>An Ethernet over RFC 2890 Generic Routing Encapsulation over IPv4
tunnel. Each tunnel must be uniquely identified by the
combination of <code>remote_ip</code>, <code>local_ip</code>, and
<code>in_key</code>. Note that if two ports are defined that are
the same except one has an optional identifier and the other does
not, the more specific one is matched first. <code>in_key</code>
is considered more specific than <code>local_ip</code> if a port
- defines one and another port defines the other. The arguments
- are:
+ defines one and another port defines the other. The following
+ options may be specified in the <ref column="options"/> column:
<dl>
<dt><code>remote_ip</code></dt>
<dd>Required. The tunnel endpoint.</dd>
either be a 32-bit number or the word <code>flow</code>. If
<code>flow</code> is specified then the key may be set using
the <code>set_tunnel</code> Nicira OpenFlow vendor extension (0
- is used in the absense of an action). The ovs-ofctl manual
+ is used in the absence of an action). The ovs-ofctl manual
page contains additional information about the Nicira OpenFlow
vendor extensions. Default is no key.</dd>
</dl>
</dl>
<dl>
<dt><code>csum</code></dt>
- <dd>Optional. Compute GRE checksums for outgoing packets and
- require checksums for incoming packets. Default is enabled,
- set to <code>false</code> to disable.</dd>
+ <dd>Optional. Compute GRE checksums on outgoing packets.
+ Checksums present on incoming packets will be validated
+ regardless of this setting. Note that GRE checksums
+ impose a significant performance penalty as they cover the
+ entire packet. As the contents of the packet is typically
+ covered by L3 and L4 checksums, this additional checksum only
+ adds value for the GRE and encapsulated Ethernet headers.
+ Default is disabled, set to <code>true</code> to enable.</dd>
+ </dl>
+ <dl>
+ <dt><code>pmtud</code></dt>
+ <dd>Optional. Enable tunnel path MTU discovery. If enabled
+ ``ICMP destination unreachable - fragmentation'' needed
+ messages will be generated for IPv4 packets with the DF bit set
+ and IPv6 packets above the minimum MTU if the packet size
+ exceeds the path MTU minus the size of the tunnel headers. It
+ also forces the encapsulating packet DF bit to be set (it is
+ always set if the inner packet implies path MTU discovery).
+ Note that this option causes behavior that is typically
+ reserved for routers and therefore is not entirely in
+ compliance with the IEEE 802.1D specification for bridges.
+ Default is enabled, set to <code>false</code> to disable.</dd>
+ </dl>
+ </dd>
+ <dt><code>capwap</code></dt>
+ <dd>Ethernet tunneling over the UDP transport portion of CAPWAP
+ (RFC 5415). This allows interoperability with certain switches
+ where GRE is not available. Note that only the tunneling component
+ of the protocol is implemented. Due to the non-standard use of
+ CAPWAP, UDP ports 58881 and 58882 are used as the source and
+ destinations ports respectivedly. Each tunnel must be uniquely
+ identified by the combination of <code>remote_ip</code> and
+ <code>local_ip</code>. If two ports are defined that are the same
+ except one includes <code>local_ip</code> and the other does not,
+ the more specific one is matched first. CAPWAP support is not
+ available on all platforms. Currently it is only supported in the
+ Linux kernel module with kernel versions >= 2.6.25. The following
+ options may be specified in the <ref column="options"/> column:
+ <dl>
+ <dt><code>remote_ip</code></dt>
+ <dd>Required. The tunnel endpoint.</dd>
+ </dl>
+ <dl>
+ <dt><code>local_ip</code></dt>
+ <dd>Optional. The destination IP that received packets must
+ match. Default is to match all addresses.</dd>
+ </dl>
+ <dl>
+ <dt><code>tos</code></dt>
+ <dd>Optional. The value of the ToS bits to be set on the
+ encapsulating packet. It may also be the word
+ <code>inherit</code>, in which case the ToS will be copied from
+ the inner packet if it is IPv4 or IPv6 (otherwise it will be
+ 0). Note that the ECN fields are always inherited. Default is
+ 0.</dd>
+ </dl>
+ <dl>
+ <dt><code>ttl</code></dt>
+ <dd>Optional. The TTL to be set on the encapsulating packet.
+ It may also be the word <code>inherit</code>, in which case the
+ TTL will be copied from the inner packet if it is IPv4 or IPv6
+ (otherwise it will be the system default, typically 64).
+ Default is the system default TTL.</dd>
</dl>
<dl>
<dt><code>pmtud</code></dt>
</dl>
</dd>
<dt><code>patch</code></dt>
- <dd>A pair of virtual devices that act as a patch cable. A
- <code>peer</code> argument is required that indicates the name
- of the other side of the patch. Since a patch must work in
- pairs, a second patch interface must be declared with the
- <code>name</code> and <code>peer</code> arguments reversed.</dd>
+ <dd>
+ <p>
+ A pair of virtual devices that act as a patch cable. The <ref
+ column="options"/> column must have the following key-value pair:
+ </p>
+ <dl>
+ <dt><code>peer</code></dt>
+ <dd>
+ The <ref column="name"/> of the <ref table="Interface"/> for
+ the other side of the patch. The named <ref
+ table="Interface"/>'s own <code>peer</code> option must specify
+ this <ref table="Interface"/>'s name. That is, the two patch
+ interfaces must have reversed <ref column="name"/> and
+ <code>peer</code> values.
+ </dd>
+ </dl>
+ </dd>
</dl>
</column>
git://git.onelab.eu / sliver-openvswitch.git / blobdiff