+
+ The ``VLAN splinters'' feature increases Open vSwitch compatibility
+ with buggy network drivers in old versions of Linux that do not
+ properly support VLANs when VLAN devices are not used, at some cost
+ in memory and performance.
+
+
+
+ When VLAN splinters are enabled on a particular interface, Open vSwitch
+ creates a VLAN device for each in-use VLAN. For sending traffic tagged
+ with a VLAN on the interface, it substitutes the VLAN device. Traffic
+ received on the VLAN device is treated as if it had been received on
+ the interface on the particular VLAN.
+
+
+
+ VLAN splinters consider a VLAN to be in use if:
+
+
+
+ -
+ The VLAN is the
value in any record.
+
+
+ -
+ The VLAN is listed within the
+ column of the record of an interface on which
+ VLAN splinters are enabled.
+
+ An empty does not influence the
+ in-use VLANs: creating 4,096 VLAN devices is impractical because it
+ will exceed the current 1,024 port per datapath limit.
+
-
+ -
+ An OpenFlow flow within any bridge matches the VLAN.
+
+
+
+
+ The same set of in-use VLANs applies to every interface on which VLAN
+ splinters are enabled. That is, the set is not chosen separately for
+ each interface but selected once as the union of all in-use VLANs based
+ on the rules above.
+
+
+
+ It does not make sense to enable VLAN splinters on an interface for an
+ access port, or on an interface that is not a physical port.
+
+
+
+ VLAN splinters are deprecated. When broken device drivers are no
+ longer in widespread use, we will delete this feature.
+
+
+
- Key-value pairs that report interface statistics. The current
- implementation updates these counters periodically. In the future,
- we plan to, instead, update them when an interface is created, when
- they are queried (e.g. using an OVSDB select
operation),
- and just before an interface is deleted due to virtual interface
- hot-unplug or VM shutdown, and perhaps at other times, but not on any
- regular periodic basis.
+ Set to true
to enable VLAN splinters on this interface.
+ Defaults to false
.
+
+
- The currently defined key-value pairs are listed below. These are
- the same statistics reported by OpenFlow in its struct
- ofp_port_stats
structure. If an interface does not support a
- given statistic, then that pair is omitted.
-
- -
- Successful transmit and receive counters:
-
- rx_packets
- - Number of received packets.
- rx_bytes
- - Number of received bytes.
- tx_packets
- - Number of transmitted packets.
- tx_bytes
- - Number of transmitted bytes.
-
-
- -
- Receive errors:
-
- rx_dropped
- - Number of packets dropped by RX.
- rx_frame_err
- - Number of frame alignment errors.
- rx_over_err
- - Number of packets with RX overrun.
- rx_crc_err
- - Number of CRC errors.
- rx_errors
- -
- Total number of receive errors, greater than or equal
- to the sum of the above.
-
-
-
- -
- Transmit errors:
-
- tx_dropped
- - Number of packets dropped by TX.
- collisions
- - Number of collisions.
- tx_errors
- -
- Total number of transmit errors, greater
- than or equal to the sum of the above.
-
-
-
-
+ VLAN splinters increase kernel and userspace memory overhead, so do
+ not use them unless they are needed.
+
+
+
+ VLAN splinters do not support 802.1p priority tags. Received
+ priorities will appear to be 0, regardless of their actual values,
+ and priorities on transmitted packets will also be cleared to 0.
+
+
+