Multicast and Routing Guide K/KA/KB.15.15

Adding an entry to the BGP neighbor table in router configuration mode
Syntax:
neighbor ipv4-addr remote-as as-#
no neighbor ipv4-addr
Adds an entry to the BGP neighbor table in router configuration mode. To remove
an entry from the table, use the no form of this command.
Specifying a neighbor with an autonomous system number that matches the
autonomous system number specified in the router bgp global
configuration command identifies the neighbor as internal to the local
autonomous system. Otherwise, the neighbor is considered external.
Exporting graceful restart capabilities to peering session
Syntax:
[no] neighbor ipv4-addr graceful-restart
Exports the graceful restart capabilities to a peering session for the ipv4 unicast
address family. Note that this feature is available only on the 8200 series devices.
Enabling or disabling dynamic capabilities
Syntax:
[no] neighbor ipv4-addr dynamic
Specifies whether to enable or disable dynamic capabilities.
BGP Dynamic Capabilities allow the communication of a change in a BGP peer’s
capabilities without having to restart the peering session. The BGP implementation
is done on a per-peer basis and in such a way that dynamic capabilities are
supported as long as the BGP peer supports BGP Dynamic Capabilities. BGP
advertises Dynamic Capabilities in the OPEN message. If a BGP peer advertises
support for BGP Dynamic Capabilities in the OPEN message, then it turns on
Dynamic Capabilities. Otherwise, the dynamic capabilities for this peer will be
disabled. BGP supports the following BGP Dynamic Capabilities:
• Graceful restart
• Route refresh
Specifying the IP address for local end of TCP connection with peer
Syntax:
[no] neighbor ipv4-addr updated-source ipv4-addr
Specifies the IP address to be used on the local end of the TCP connection with the
peer. This is the address of a broadcast, NBMA or loopback interface and the local
address of a point-to-point interface. For external peers, the local address must be
on an interface that is shared with the peer or with the peer’s gateway when a
gateway is used. A session with an external peer will be opened only when an
interface with the appropriate local address (through which the peer or gateway
address is directly reachable) is operating. For internal peers, a peer session will
be maintained when any interface with the specified local address is operating. In
any case, an incoming connection will be recognized as a match for a configured
peer only if it is addressed to the configured local address.
298 Border Gateway Protocol (BGP)