--- zzzz-none-000/linux-3.10.107/Documentation/networking/vxlan.txt 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/Documentation/networking/vxlan.txt 2021-02-04 17:41:59.000000000 +0000 @@ -1,32 +1,36 @@ Virtual eXtensible Local Area Networking documentation ====================================================== -The VXLAN protocol is a tunnelling protocol that is designed to -solve the problem of limited number of available VLAN's (4096). -With VXLAN identifier is expanded to 24 bits. - -It is a draft RFC standard, that is implemented by Cisco Nexus, -Vmware and Brocade. The protocol runs over UDP using a single -destination port (still not standardized by IANA). -This document describes the Linux kernel tunnel device, -there is also an implantation of VXLAN for Openvswitch. - -Unlike most tunnels, a VXLAN is a 1 to N network, not just point -to point. A VXLAN device can either dynamically learn the IP address -of the other end, in a manner similar to a learning bridge, or the -forwarding entries can be configured statically. - -The management of vxlan is done in a similar fashion to it's -too closest neighbors GRE and VLAN. Configuring VXLAN requires -the version of iproute2 that matches the kernel release -where VXLAN was first merged upstream. +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 li add vxlan0 type vxlan id 42 group 239.1.1.1 dev eth1 + # ip link add vxlan0 type vxlan id 42 group 239.1.1.1 dev eth1 dstport 4789 -This creates a new device (vxlan0). The device uses the -the multicast group 239.1.1.1 over eth1 to handle packets where -no entry is in the forwarding table. +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