From 4abded8025a47990e58cd0a5fe9b96e38f4a3715 Mon Sep 17 00:00:00 2001 From: rebortg Date: Sun, 29 Nov 2020 21:52:28 +0100 Subject: arrange: interfaces --- docs/interfaces/vxlan.rst | 295 ---------------------------------------------- 1 file changed, 295 deletions(-) delete mode 100644 docs/interfaces/vxlan.rst (limited to 'docs/interfaces/vxlan.rst') diff --git a/docs/interfaces/vxlan.rst b/docs/interfaces/vxlan.rst deleted file mode 100644 index 40dc5400..00000000 --- a/docs/interfaces/vxlan.rst +++ /dev/null @@ -1,295 +0,0 @@ -.. _vxlan-interface: - -##### -VXLAN -##### - -:abbr:`VXLAN (Virtual Extensible LAN)` is a network virtualization technology -that attempts to address the scalability problems associated with large cloud -computing deployments. It uses a VLAN-like encapsulation technique to -encapsulate OSI layer 2 Ethernet frames within layer 4 UDP datagrams, using -4789 as the default IANA-assigned destination UDP port number. VXLAN -endpoints, which terminate VXLAN tunnels and may be either virtual or physical -switch ports, are known as :abbr:`VTEPs (VXLAN tunnel endpoints)`. - -VXLAN is an evolution of efforts to standardize on an overlay encapsulation -protocol. It increases scalability up to 16 million logical networks and -allows for layer 2 adjacency across IP networks. Multicast or unicast with -head-end replication (HER) is used to flood broadcast, unknown unicast, -and multicast (BUM) traffic. - -The VXLAN specification was originally created by VMware, Arista Networks -and Cisco. Other backers of the VXLAN technology include Huawei, Broadcom, -Citrix, Pica8, Big Switch Networks, Cumulus Networks, Dell EMC, Ericsson, -Mellanox, FreeBSD, OpenBSD, Red Hat, Joyent, and Juniper Networks. - -VXLAN was officially documented by the IETF in :rfc:`7348`. - -If configuring VXLAN in a VyOS virtual machine, ensure that MAC spoofing -(Hyper-V) or Forged Transmits (ESX) are permitted, otherwise forwarded frames -may be blocked by the hypervisor. - -.. note:: As VyOS is based on Linux and there was no official IANA port assigned - for VXLAN, VyOS uses a default port of 8472. You can change the port on a - per VXLAN interface basis to get it working across multiple vendors. - -Configuration -============= - -Common interface configuration ------------------------------- - -.. cmdinclude:: ../_include/interface-common-without-dhcp.txt - :var0: vxlan - :var1: vxlan0 - -VXLAN specific options ------------------------ - -.. cfgcmd:: set interfaces vxlan vni - - Each VXLAN segment is identified through a 24-bit segment ID, termed the - :abbr:`VNI (VXLAN Network Identifier (or VXLAN Segment ID))`, This allows - up to 16M VXLAN segments to coexist within the same administrative domain. - -.. cfgcmd:: set interfaces vxlan port - - Configure port number of remote VXLAN endpoint. - - .. note:: As VyOS is Linux based the default port used is not using 4789 - as the default IANA-assigned destination UDP port number. Instead VyOS - uses the Linux default port of 8472. - -.. cfgcmd:: set interfaces vxlan source-address - - Source IP address used for VXLAN underlay. This is mandatory when using VXLAN - via L2VPN/EVPN. - -Unicast -^^^^^^^ - -.. cfgcmd:: set interfaces vxlan remote
- - IPv4/IPv6 remote address of the VXLAN tunnel. Alternative to multicast, the - remote IPv4/IPv6 address can set directly. - -Multicast -^^^^^^^^^ - -.. cfgcmd:: set interfaces vxlan source-interface - - Interface used for VXLAN underlay. This is mandatory when using VXLAN via - a multicast network. VXLAN traffic will always enter and exit this interface. - - -.. cfgcmd:: set interfaces vxlan group
- - Multicast group address for VXLAN interface. VXLAN tunnels can be built - either via Multicast or via Unicast. - - Both IPv4 and IPv6 multicast is possible. - -Multicast VXLAN -=============== - -Topology: PC4 - Leaf2 - Spine1 - Leaf3 - PC5 - -PC4 has IP 10.0.0.4/24 and PC5 has IP 10.0.0.5/24, so they believe they are in -the same broadcast domain. - -Let's assume PC4 on Leaf2 wants to ping PC5 on Leaf3. Instead of setting Leaf3 -as our remote end manually, Leaf2 encapsulates the packet into a UDP-packet and -sends it to its designated multicast-address via Spine1. When Spine1 receives -this packet it forwards it to all other Leafs who has joined the same -multicast-group, in this case Leaf3. When Leaf3 receives the packet it forwards -it, while at the same time learning that PC4 is reachable behind Leaf2, because -the encapsulated packet had Leaf2's IP-address set as source IP. - -PC5 receives the ping echo, responds with an echo reply that Leaf3 receives and -this time forwards to Leaf2's unicast address directly because it learned the -location of PC4 above. When Leaf2 receives the echo reply from PC5 it sees that -it came from Leaf3 and so remembers that PC5 is reachable via Leaf3. - -Thanks to this discovery, any subsequent traffic between PC4 and PC5 will not -be using the multicast-address between the Leafs as they both know behind which -Leaf the PCs are connected. This saves traffic as less multicast packets sent -reduces the load on the network, which improves scalability when more Leafs are -added. - -For optimal scalability Multicast shouldn't be used at all, but instead use BGP -to signal all connected devices between leafs. Unfortunately, VyOS does not yet -support this. - -Example -------- - -The setup is this: Leaf2 - Spine1 - Leaf3 - -Spine1 is a Cisco IOS router running version 15.4, Leaf2 and Leaf3 is each a -VyOS router running 1.2. - -This topology was built using GNS3. - -Topology: - -.. code-block:: none - - Spine1: - fa0/2 towards Leaf2, IP-address: 10.1.2.1/24 - fa0/3 towards Leaf3, IP-address: 10.1.3.1/24 - - Leaf2: - Eth0 towards Spine1, IP-address: 10.1.2.2/24 - Eth1 towards a vlan-aware switch - - Leaf3: - Eth0 towards Spine1, IP-address 10.1.3.3/24 - Eth1 towards a vlan-aware switch - -**Spine1 Configuration:** - -.. code-block:: none - - conf t - ip multicast-routing - ! - interface fastethernet0/2 - ip address 10.1.2.1 255.255.255.0 - ip pim sparse-dense-mode - ! - interface fastethernet0/3 - ip address 10.1.3.1 255.255.255.0 - ip pim sparse-dense-mode - ! - router ospf 1 - network 10.0.0.0 0.255.255.255 area 0 - -Multicast-routing is required for the leafs to forward traffic between each -other in a more scalable way. This also requires PIM to be enabled towards the -Leafs so that the Spine can learn what multicast groups each Leaf expect -traffic from. - -**Leaf2 configuration:** - -.. code-block:: none - - set interfaces ethernet eth0 address '10.1.2.2/24' - set protocols ospf area 0 network '10.0.0.0/8' - - ! Our first vxlan interface - set interfaces bridge br241 address '172.16.241.1/24' - set interfaces bridge br241 member interface 'eth1.241' - set interfaces bridge br241 member interface 'vxlan241' - - set interfaces vxlan vxlan241 group '239.0.0.241' - set interfaces vxlan vxlan241 source-interface 'eth0' - set interfaces vxlan vxlan241 vni '241' - - ! Our seconds vxlan interface - set interfaces bridge br242 address '172.16.242.1/24' - set interfaces bridge br242 member interface 'eth1.242' - set interfaces bridge br242 member interface 'vxlan242' - - set interfaces vxlan vxlan242 group '239.0.0.242' - set interfaces vxlan vxlan242 source-interface 'eth0' - set interfaces vxlan vxlan242 vni '242' - -**Leaf3 configuration:** - -.. code-block:: none - - set interfaces ethernet eth0 address '10.1.3.3/24' - set protocols ospf area 0 network '10.0.0.0/8' - - ! Our first vxlan interface - set interfaces bridge br241 address '172.16.241.1/24' - set interfaces bridge br241 member interface 'eth1.241' - set interfaces bridge br241 member interface 'vxlan241' - - set interfaces vxlan vxlan241 group '239.0.0.241' - set interfaces vxlan vxlan241 source-interface 'eth0' - set interfaces vxlan vxlan241 vni '241' - - ! Our seconds vxlan interface - set interfaces bridge br242 address '172.16.242.1/24' - set interfaces bridge br242 member interface 'eth1.242' - set interfaces bridge br242 member interface 'vxlan242' - - set interfaces vxlan vxlan242 group '239.0.0.242' - set interfaces vxlan vxlan242 source-interface 'eth0' - set interfaces vxlan vxlan242 vni '242' - -As you can see, Leaf2 and Leaf3 configuration is almost identical. There are -lots of commands above, I'll try to into more detail below, command -descriptions are placed under the command boxes: - -.. code-block:: none - - set interfaces bridge br241 address '172.16.241.1/24' - -This commands creates a bridge that is used to bind traffic on eth1 vlan 241 -with the vxlan241-interface. The IP-address is not required. It may however be -used as a default gateway for each Leaf which allows devices on the vlan to -reach other subnets. This requires that the subnets are redistributed by OSPF -so that the Spine will learn how to reach it. To do this you need to change the -OSPF network from '10.0.0.0/8' to '0.0.0.0/0' to allow 172.16/12-networks to be -advertised. - -.. code-block:: none - - set interfaces bridge br241 member interface 'eth1.241' - set interfaces bridge br241 member interface 'vxlan241' - -Binds eth1.241 and vxlan241 to each other by making them both member interfaces of -the same bridge. - -.. code-block:: none - - set interfaces vxlan vxlan241 group '239.0.0.241' - -The multicast-group used by all Leafs for this vlan extension. Has to be the -same on all Leafs that has this interface. - -.. code-block:: none - - set interfaces vxlan vxlan241 source-interface 'eth0' - -Sets the interface to listen for multicast packets on. Could be a loopback, not -yet tested. - -.. code-block:: none - - set interfaces vxlan vxlan241 vni '241' - -Sets the unique id for this vxlan-interface. Not sure how it correlates with -multicast-address. - -.. code-block:: none - - set interfaces vxlan vxlan241 port 12345 - -The destination port used for creating a VXLAN interface in Linux defaults to -its pre-standard value of 8472 to preserve backwards compatibility. A -configuration directive to support a user-specified destination port to override -that behavior is available using the above command. - -Unicast VXLAN -============= - -Alternative to multicast, the remote IPv4 address of the VXLAN tunnel can be -set directly. Let's change the Multicast example from above: - -.. code-block:: none - - # leaf2 and leaf3 - delete interfaces vxlan vxlan241 group '239.0.0.241' - delete interfaces vxlan vxlan241 source-interface 'eth0' - - # leaf2 - set interface vxlan vxlan241 remote 10.1.3.3 - - # leaf3 - set interface vxlan vxlan241 remote 10.1.2.2 - -The default port udp is set to 8472. -It can be changed with ``set interface vxlan port `` -- cgit v1.2.3