| 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 |