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diff --git a/docs/routing/mpls.rst b/docs/routing/mpls.rst deleted file mode 100644 index 82e99a17..00000000 --- a/docs/routing/mpls.rst +++ /dev/null @@ -1,157 +0,0 @@ -.. _mpls: - -#################################### -MPLS (Multiprotocol Label Switching) -#################################### - -:abbr:`MPLS (Multi-Protocol Label Switching)` is a packet forwarding paradigm -which differs from regular IP forwarding. Instead of IP addresses being used to -make the decision on finding the exit interface, a router will instead use an -exact match on a 32 bit/4 byte header called the MPLS label. This label is -inserted between the ethernet (layer 2) header and the IP (layer 3) header. -One can statically or dynamically assign label allocations, but we will focus -on dynamic allocation of labels using some sort of label distribution protocol -(such as the aptly named Label Distribution Protocol / LDP, Resource Reservation -Protocol / RSVP, or Segment Routing through OSPF/ISIS). These protocols allow -for the creation of a unidirectional/unicast path called a labeled switched -path (initialized as LSP) throughout the network that operates very much like -a tunnel through the network. An easy way of thinking about how an MPLS LSP -actually forwards traffic throughout a network is to think of a GRE tunnel. -They are not the same in how they operate, but they are the same in how they -handle the tunneled packet. It would be good to think of MPLS as a tunneling -technology that can be used to transport many different types of packets, to -aid in traffic engineering by allowing one to specify paths throughout the -network (using RSVP or SR), and to generally allow for easier intra/inter -network transport of data packets. - -For more information on how MPLS label switching works, please go visit -`Wikipedia (MPLS)`_. - -.. note:: MPLS support in VyOS is not finished yet, and therefore its - functionality is limited. Currently there is no support for MPLS enabled VPN - services such as L3VPNs, L2VPNs, and mVPNs. RSVP support is also not present - as the underlying routing stack (FRR) does not implement it. Currently VyOS - can be configured as a label switched router (MPLS P router), in both - penultimate and ultimate hop popping operations. - -Label Distribution Protocol -=========================== - -The :abbr:`MPLS (Multi-Protocol Label Switching)` architecture does not assume -a single protocol to create MPLS paths. VyOS supports the Label Distribution -Protocol (LDP) as implemented by FRR, based on :rfc:`5036`. - -:abbr:`LDP (Label Distribution Protocol)` is a TCP based MPLS signaling protocol -that distributes labels creating MPLS label switched paths in a dynamic manner. -LDP is not a routing protocol, as it relies on other routing protocols for -forwarding decisions. LDP cannot bootstrap itself, and therefore relies on said -routing protocols for communication with other routers that use LDP. - -In order to allow for LDP on the local router to exchange label advertisements -with other routers, a TCP session will be established between automatically -discovered and statically assigned routers. LDP will try to establish a TCP -session to the **transport address** of other routers. Therefore for LDP to -function properly please make sure the transport address is shown in the -routing table and reachable to traffic at all times. - -It is highly recommended to use the same address for both the LDP router-id and -the discovery transport address, but for VyOS MPLS LDP to work both parameters -must be explicitly set in the configuration. - -Configuration Options -===================== - -.. cfgcmd:: set protocols mpls ldp interface <interface> - - Use this command to enable LDP, and enable MPLS processing on the interface you - define. - -.. cfgcmd:: set protocols mpls ldp router-id <address> - - Use this command to configure the IP address used as the LDP router-id of the - local device. - -.. cfgcmd:: set protocols mpls ldp discovery transport-ipv4-address <IPv4 address> -.. cfgcmd:: set protocols mpls ldp discovery transport-ipv6-address <IPv6 address> - - Use this command to set the IPv4 or IPv6 transport-address used by LDP. - -.. cfgcmd:: set protocols mpls ldp neighbor <IPv4 address> password <password> - - Use this command to configure authentication for LDP peers. Set the - IP address of the LDP peer and a password that should be shared in - order to become neighbors. - -.. cfgcmd:: set protocols mpls ldp discovery hello-interval <seconds> -.. cfgcmd:: set protocols mpls ldp discovery hello-holdtime <seconds> - - Use this command if you would like to set the discovery hello and hold time - parameters. - -.. cfgcmd:: set protocols mpls ldp discovery session-ipv4-holdtime <seconds> -.. cfgcmd:: set protocols mpls ldp discovery session-ipv6-holdtime <seconds> - - Use this command if you would like to set the TCP session hold time intervals. - -.. cfgcmd:: set protocols mpls ldp export ipv4 explicit-null -.. cfgcmd:: set protocols mpls ldp export ipv6 explicit-null - - Use this command if you would like for the router to advertise FECs with a label - of 0 for explicit null operations. - - -Sample configuration to setup LDP on VyOS ------------------------------------------ - -.. code-block:: none - - set protocols ospf area 0 network '192.168.255.252/32' <--- Routing for loopback - set protocols ospf area 0 network '192.168.0.5/32' <--- Routing for an interface connecting to the network - set protocols ospf parameters router-id '192.168.255.252' <--- Router ID setting for OSPF - set protocols mpls ldp discovery transport-ipv4-address '192.168.255.252' <--- Transport address for LDP for TCP sessions to connect to - set protocols mpls ldp interface 'eth1' <--- Enable MPLS and LDP for an interface connecting to network - set protocols mpls ldp interface 'lo' <--- Enable MPLS and LDP on loopback for future services connectivity - set protocols mpls ldp router-id '192.168.255.252' <--- Router ID setting for LDP - set interfaces ethernet eth1 address '192.168.0.5/31' <--- Interface IP for connecting to network - set interfaces loopback lo address '192.168.255.252/32' <--- Interface loopback IP for router ID and other uses - - -Operational Mode Commands -========================= - -When LDP is working, you will be able to see label information in the outcome -of ``show ip route``. Besides that information, there are also specific *show* -commands for LDP: - -Show ----- - -.. opcmd:: show mpls ldp binding - - Use this command to see the Label Information Base. - -.. opcmd:: show mpls ldp discovery - - Use this command to see discovery hello information - -.. opcmd:: show mpls ldp interface - - Use this command to see LDP interface information - -.. opcmd:: show mpls ldp neighbor - - Use this command to see LDP neighbor information - -.. opcmd:: show mpls ldp neighbor detail - - Use this command to see detailed LDP neighbor information - -Reset ------ - -.. opcmd:: reset mpls ldp neighbor <IPv4 or IPv6 address> - - Use this command to reset an LDP neighbor/TCP session that is established - - -.. _`Wikipedia (MPLS)`: https://en.wikipedia.org/wiki/Multiprotocol_Label_Switching |