BGP4+

In this section:

  1. BGP4+ overview
    The implementation of IPv6 supports multiprotocol BGP (MBGP) extensions that allow Border Gateway Protocol version 4 plus (BGP4+) to distribute routing information. BGP4+ supports all of the same features and functionality as IPv4 BGP (BGP4).
  2. BGP global mode
    Configurations that are not specific to address family configuration are available in the BGP global configuration mode.
  3. IPv6 unicast address family
    The IPv6 unicast address family configuration level provides access to commands that allow you to configure BGP4+ unicast routes. The commands that you enter at this level apply only to the IPv6 unicast address family.
  4. BGP4+ neighbors
    BGP4+ neighbors can be configured using link-local addresses or global addresses.
  5. BGP4+ Peer Groups
    Neighbors having the same attributes and parameters can be grouped together by means of the neighbor peer-group command.
  6. Importing routes into BGP4+
    Routes can be explicitly specified for advertisement by BGP.
  7. Advertising the default BGP4+ route
    A BGP device can be configured to advertise the default IPv6 route to all BGP4+ neighbors and to install that route in the local BGP4+ route table.
  8. Advertising the default BGP4+ route to a specific neighbor
    A BGP device can be configured to advertise the default IPv6 route to a specific neighbor.
  9. Using the IPv6 Default Route as a Valid Next Hop for a BGP4+ Route
    In certain cases, such as when a device is acting as an edge device, it can be configured to use the default route as a valid next hop.
  10. BGP4+ next hop recursion
    A device can find the IGP route to the next-hop gateway for a BGP4+ route.
  11. BGP4+ NLRIs and next hop attributes
    BGP4+ introduces new attributes to handle multiprotocol extensions for BGP.
  12. BGP4+ route reflection
  13. BGP4+ route aggregation
    A device can be configured to aggregate routes in a range of networks into a single IPv6 prefix.
  14. BGP4+ multipath
    The BGP4+ multipath feature can be used to enable load-balancing across different paths.
  15. Route maps
    Route maps must be applied to IPv6 unicast address prefixes in IPv6 address family configuration mode.
  16. Redistributing prefixes into BGP4+
    Various routes can be redistributed into BGP.
  17. Redistributing routes into BGP4+
    Various routes can be redistributed into BGP. This task redistributes connected routes into BGP.
  18. Specifying the weight added to BGP4+ received routes
    The weight that the device adds to received routes can be specified. The following task changes the weight from the default for routes that are received from a specified BGP4+ neighbor.
  19. BGP4+ outbound route filtering
    The BGP4+ Outbound Route Filtering Capability (ORF) feature is used to minimize the number of BGP updates sent between BGP peers.
  20. BGP4+ confederations
    A large autonomous system (AS) can be divided into multiple subautonomous systems and grouped into a single BGP4+ confederation.
  21. BGP4+ extended community
    The BGP4+ extended community feature filters routes based on a regular expression specified when a route has multiple community values in it.
  22. BGP4+ graceful restart
    BGP4+ graceful restart (GR) allows for restarts where BGP neighboring devices participate in the restart, helping to ensure that no route and topology changes occur in the network for the duration of the restart.
  23. Generalized TTL Security Mechanism support
    Generalized TTL Security Mechanism (GTSM) is a lightweight security mechanism that protects external Border Gateway Protocol (eBGP) peering sessions from CPU utilization-based attacks using forged IP packets. GTSM prevents attempts to hijack the eBGP peering session by a host on a network segment that is not part of either BGP network, or by a host on a network segment that is not between the eBGP peers.
  24. Disabling the BGP AS_PATH Check Function
    A device can be configured so that the AS_PATH check function for routes learned from a specific location is disabled, and routes that contain the recipient BGP speaker's AS number are not rejected.
  25. Displaying BGP4+ statistics
    Various show ipv6 bgp commands verify information about BGP4+ configurations.
  26. Displaying BGP4+ Neighbor Statistics
    Various show ipv6 bgp neighbors commands verify information about BGP4+ neighbor configurations.