Multicast and Routing Guide K/KA/KB.15.15

Configuring BGP route attributes
Prerequisites
Before configuring this task, you should have configured BGP basic functions.
Configuration procedure
You can configure BGP route attributes to influence BGP route selection.
Follow these steps to configure BGP route attributes.
RemarksUse the command...To do...
configurationEnter global configuration context
bgp as-numberEnter BGP context
Optional. The default preferences of
external, internal, and local routes are
20, 200, and 200 respectively.
preference
{external-preference
internal-preference
local-preference}
Configure preferences for external,
internal, local routes
Optionalneighbor {ip-address} weight
{weight}
Configure weight to be assigned to
received routes from a peer
Optional. By default, advertisements to
an eBGP peer take the router as the
neighbor {ip-address}
next-hop-self
Specify the router as the next hop of
routes sent to a peer
next hop, while advertisements to an
iBGP peer do not take the local router
as the next hop.
Configure the AS_PATH attribute:
Optional. The local AS number cannot
be repeated in routes from the peer.
neighbor {ip-address}
allow-as-in [number]
Configure repeating times of local AS
number in routes from a peer
Optional. Not specified by default This
command is only applicable to an
eBGP peer.
neighbor {ip-address}
local-as as-number
Specify a fake AS number for a peer
Optional. The substitution is not
configured by default.
neighbor {ip-address}
as-override
Substitute local AS number for the AS
number of a peer in the AS_PATH
attribute
Optional. By default, BGP updates
carry private AS numbers.
neighbor {ip-address}
remove-private-as
Configure BGP to not keep private AS
numbers in the AS_PATH attribute of
updates to a peer
BGP basic configuration 313