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.
Unified · Split
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| 1 | Virtual eXtensible Local Area Networking documentation | 1 | Virtual eXtensible Local Area Networking documentation |
| 2 | ====================================================== | 2 | ====================================================== |
| 3 | 3 | ||
| 4 | The VXLAN protocol is a tunnelling protocol that is designed to | 4 | The VXLAN protocol is a tunnelling protocol designed to solve the |
| 5 | solve the problem of limited number of available VLAN's (4096). | 5 | problem of limited VLAN IDs (4096) in IEEE 802.1q. With VXLAN the |
| 6 | With VXLAN identifier is expanded to 24 bits. | 6 | size of the identifier is expanded to 24 bits (16777216). |
| 7 | 7 | ||
| 8 | It is a draft RFC standard, that is implemented by Cisco Nexus, | 8 | VXLAN is described by IETF RFC 7348, and has been implemented by a |
| 9 | Vmware and Brocade. The protocol runs over UDP using a single | 9 | number of vendors. The protocol runs over UDP using a single |
| 10 | destination port (still not standardized by IANA). | 10 | destination port. This document describes the Linux kernel tunnel |
| 11 | This document describes the Linux kernel tunnel device, | 11 | device, there is also a separate implementation of VXLAN for |
| 12 | there is also an implantation of VXLAN for Openvswitch. | 12 | Openvswitch. |
| 13 | 13 | ||
| 14 | Unlike most tunnels, a VXLAN is a 1 to N network, not just point | 14 | Unlike most tunnels, a VXLAN is a 1 to N network, not just point to |
| 15 | to point. A VXLAN device can either dynamically learn the IP address | 15 | point. A VXLAN device can learn the IP address of the other endpoint |
| 16 | of the other end, in a manner similar to a learning bridge, or the | 16 | either dynamically in a manner similar to a learning bridge, or make |
| 17 | forwarding entries can be configured statically. | 17 | use of statically-configured forwarding entries. |
| 18 | 18 | ||
| 19 | The management of vxlan is done in a similar fashion to it's | 19 | The management of vxlan is done in a manner similar to its two closest |
| 20 | too closest neighbors GRE and VLAN. Configuring VXLAN requires | 20 | neighbors GRE and VLAN. Configuring VXLAN requires the version of |
| 21 | the version of iproute2 that matches the kernel release | 21 | iproute2 that matches the kernel release where VXLAN was first merged |
| 22 | where VXLAN was first merged upstream. | 22 | upstream. |
| 23 | 23 | ||
| 24 | 1. Create vxlan device | 24 | 1. Create vxlan device |
| 25 | # ip li add vxlan0 type vxlan id 42 group 239.1.1.1 dev eth1 | 25 | # ip link add vxlan0 type vxlan id 42 group 239.1.1.1 dev eth1 dstport 4789 |
| 26 | 26 | ||
| 27 | This creates a new device (vxlan0). The device uses the | 27 | This creates a new device named vxlan0. The device uses the multicast |
| 28 | the multicast group 239.1.1.1 over eth1 to handle packets where | 28 | group 239.1.1.1 over eth1 to handle traffic for which there is no |
| 29 | no entry is in the forwarding table. | 29 | entry in the forwarding table. The destination port number is set to |
| 30 | the IANA-assigned value of 4789. The Linux implementation of VXLAN | ||
| 31 | pre-dates the IANA's selection of a standard destination port number | ||
| 32 | and uses the Linux-selected value by default to maintain backwards | ||
| 33 | compatibility. | ||
| 30 | 34 | ||
| 31 | 2. Delete vxlan device | 35 | 2. Delete vxlan device |
| 32 | # ip link delete vxlan0 | 36 | # ip link delete vxlan0 |