Configuring the as-path attribute – H3C Technologies H3C S7500E Series Switches User Manual
Page 245
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In a “third party next hop" network, that is, the local router has two multicast eBGP peers in a
broadcast network, the router does not specify itself as the next hop of routing information sent to the
eBGP peers unless the peer next-hop-local command is configured.
Follow these steps to specify the router as the next hop of routes sent to a peer/peer group:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enter BGP view
bgp as-number
—
Enter IPv4 MBGP address family
view
ipv4-family multicast
—
Specify the router as the next hop of
routes sent to a peer/peer group
peer { group-name | ip-address }
next-hop-local
Optional
By default, the next hop of
routes sent to a MBGP
eBGP peer/peer group is
the advertising router, while
that of routes sent to a
MBGP iBGP peer/peer
group is not.
Configuring the AS-PATH Attribute
In general, MBGP checks whether the AS_PATH attribute of a route from a peer contains the local AS
number. If yes, it discards the route to avoid routing loops.
Follow these steps to configure the AS-PATH attribute:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enter BGP view
bgp as-number
—
Enter IPv4 MBGP address family view
ipv4-family multicast
—
Specify the maximum
number of times the local
AS number can appear
in routes from the
peer/peer group
peer { group-name | ip-address }
allow-as-loop [ number ]
Optional
By default, the local AS
number can not appear in
routes from a peer/peer
group.
Configure the
AS_PATH
attribute
Disable BGP from
considering the
AS_PATH during best
route selection
bestroute as-path-neglect
Optional
By default, BGP considers
AS_PATH during best
route selection.