mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-29 23:53:32 +00:00
e8fed985d7
A few things have changed since the previous version of the vxlan documentation was written, so update it and correct some grammar and such while we are at it. Signed-off-by: Rick Jones <rick.jones2@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
51 lines
2 KiB
Text
51 lines
2 KiB
Text
Virtual eXtensible Local Area Networking documentation
|
|
======================================================
|
|
|
|
The VXLAN protocol is a tunnelling protocol designed to solve the
|
|
problem of limited VLAN IDs (4096) in IEEE 802.1q. With VXLAN the
|
|
size of the identifier is expanded to 24 bits (16777216).
|
|
|
|
VXLAN is described by IETF RFC 7348, and has been implemented by a
|
|
number of vendors. The protocol runs over UDP using a single
|
|
destination port. This document describes the Linux kernel tunnel
|
|
device, there is also a separate implementation of VXLAN for
|
|
Openvswitch.
|
|
|
|
Unlike most tunnels, a VXLAN is a 1 to N network, not just point to
|
|
point. A VXLAN device can learn the IP address of the other endpoint
|
|
either dynamically in a manner similar to a learning bridge, or make
|
|
use of statically-configured forwarding entries.
|
|
|
|
The management of vxlan is done in a manner similar to its two closest
|
|
neighbors GRE and VLAN. Configuring VXLAN requires the version of
|
|
iproute2 that matches the kernel release where VXLAN was first merged
|
|
upstream.
|
|
|
|
1. Create vxlan device
|
|
# ip link add vxlan0 type vxlan id 42 group 239.1.1.1 dev eth1 dstport 4789
|
|
|
|
This creates a new device named vxlan0. The device uses the multicast
|
|
group 239.1.1.1 over eth1 to handle traffic for which there is no
|
|
entry in the forwarding table. The destination port number is set to
|
|
the IANA-assigned value of 4789. The Linux implementation of VXLAN
|
|
pre-dates the IANA's selection of a standard destination port number
|
|
and uses the Linux-selected value by default to maintain backwards
|
|
compatibility.
|
|
|
|
2. Delete vxlan device
|
|
# ip link delete vxlan0
|
|
|
|
3. Show vxlan info
|
|
# ip -d link show vxlan0
|
|
|
|
It is possible to create, destroy and display the vxlan
|
|
forwarding table using the new bridge command.
|
|
|
|
1. Create forwarding table entry
|
|
# bridge fdb add to 00:17:42:8a:b4:05 dst 192.19.0.2 dev vxlan0
|
|
|
|
2. Delete forwarding table entry
|
|
# bridge fdb delete 00:17:42:8a:b4:05 dev vxlan0
|
|
|
|
3. Show forwarding table
|
|
# bridge fdb show dev vxlan0
|