Concept Guide

Enabling MBGP Congurations
Multiprotocol BGP (MBGP) is an enhanced BGP that carries IP multicast routes. BGP carries two sets of routes: one set for unicast routing
and one set for multicast routing. The routes associated with multicast routing are used by the protocol independent multicast (PIM) to
build data distribution trees.
Dell EMC Networking OS MBGP is implemented per RFC 1858. You can enable the MBGP feature per router and/or per peer/peer-group.
The default is IPv4 Unicast routes.
When you congure a peer to support IPv4 multicast, Dell EMC Networking OS takes the following actions:
• Send a capacity advertisement to the peer in the BGP Open message specifying IPv4 multicast as a supported AFI/SAFI (Subsequent
Address Family Identier).
• If the corresponding capability is received in the peer’s Open message, BGP marks the peer as supporting the AFI/SAFI.
• When exchanging updates with the peer, BGP sends and receives IPv4 multicast routes if the peer is marked as supporting that AFI/
SAFI.
• Exchange of IPv4 multicast route information occurs through the use of two new attributes called MP_REACH_NLRI and
MP_UNREACH_NLRI, for feasible and withdrawn routes, respectively.
• If the peer has not been activated in any AFI/SAFI, the peer remains in Idle state.
Most Dell EMC Networking OS BGP IPv4 unicast commands are extended to support the IPv4 multicast RIB using extra options to the
command. For a detailed description of the MBGP commands, refer to the
Dell EMC Networking OS Command Line Interface Reference
Guide.
MBGP support for IPv6
MBGP suports IPv6 with same features and functionality as IPv4 BGP.
MBGP for IPv6 supports IPv6 address-family and Network Layer Reachability Information (NLRI) and next hop that uses IPv6 address.
Conguring IPv6 MBGP between peers
To congure IPv6 MBGP, use the following commands.
Following are the steps to congure IPv6 MBGP between two peers. The neighbors that are congured using neighbor remote-as
command exchange only the IPv4 unicast address prexes. In order to exchange IPv6 address prexes, you have to activate the neighbors
using
neighbor active command inside the address-family conguration.
• Enter the router conguration mode and the AS number.
CONFIG mode
router bgp as-number
• Add the IP address of the neighbor for the specied autonomous system.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6–address | peer-group-name} remote-as as-number
• Specify the IPv6 address family conguration.
CONFIG-ROUTER-BGP mode
address-family ipv6 [unicast | vrf vrf-name]
unicast — Species the IPv6 unicast address family. The default address-family is IPv6 unicast.
vrf vrf-name — Species the name of VRF instance associated with the IPv6 address-family conguration.
• Enable the neighbor to exchange prexes for IPv6 unicast address family.
CONFIG-ROUTER-BGP-AF (Address Family) mode
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Border Gateway Protocol (BGP)