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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /Documentation/networking/vxlan.rst | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'Documentation/networking/vxlan.rst')
| -rw-r--r-- | Documentation/networking/vxlan.rst | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/Documentation/networking/vxlan.rst b/Documentation/networking/vxlan.rst new file mode 100644 index 000000000..2759dc1cc --- /dev/null +++ b/Documentation/networking/vxlan.rst @@ -0,0 +1,88 @@ +.. SPDX-License-Identifier: GPL-2.0 + +====================================================== +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 + +The following NIC features may indicate support for UDP tunnel-related +offloads (most commonly VXLAN features, but support for a particular +encapsulation protocol is NIC specific): + + - `tx-udp_tnl-segmentation` + - `tx-udp_tnl-csum-segmentation` + ability to perform TCP segmentation offload of UDP encapsulated frames + + - `rx-udp_tunnel-port-offload` + receive side parsing of UDP encapsulated frames which allows NICs to + perform protocol-aware offloads, like checksum validation offload of + inner frames (only needed by NICs without protocol-agnostic offloads) + +For devices supporting `rx-udp_tunnel-port-offload` the list of currently +offloaded ports can be interrogated with `ethtool`:: + + $ ethtool --show-tunnels eth0 + Tunnel information for eth0: + UDP port table 0: + Size: 4 + Types: vxlan + No entries + UDP port table 1: + Size: 4 + Types: geneve, vxlan-gpe + Entries (1): + port 1230, vxlan-gpe |
