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Configuring the med attribute – H3C Technologies H3C S12500 Series Switches User Manual

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Configure IPv6 BGP basic functions.

Configuring IPv6 BGP preference and default LOCAL_PREF
and NEXT_HOP attributes

Follow these guidelines when you configure IPv6 BGP preference and default LOCAL_PREF and

NEXT_HOP attributes:

To ensure an IBGP peer can find the correct next hop, you can configure routes advertised to the
IPv6 IBGP peer or peer group to use the local router as the next hop. If BGP load balancing is

configured, the local router specifies itself as the next hop of routes sent to an IPv6 IBGP peer or
peer group regardless of whether the peer next-hop-local command is configured.

In a "third party next hop" network where the two IPv6 EBGP peers reside in a common broadcast
subnet, the router does not change the next hop for routes sent to the IPv6 EBGP peer or peer group

by default, unless the peer next-hop-local command is configured.

To configure IPv6 BGP preference and default LOCAL_PREF and NEXT_HOP attributes:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view.

bgp as-number

N/A

3.

Enter IPv6 address family view

or IPv6 BGP-VPN instance
view.

ipv6-family [ vpn-instance
vpn-instance-name ]

N/A

4.

Configure preference values
for IPv6 BGP external,

internal, local routes.

preference { external-preference
internal-preference

local-preference | route-policy
route-policy-name }

Optional.
The default preference values of
external, internal, and local routes are

255, 255, and 130.

5.

Configure the default local
preference.

default local-preference value

Optional.
The value defaults to 100.

6.

Advertise routes to an IPv6
peer or peer group with the

local router as the next hop.

peer { group-name |
ipv6-address
} next-hop-local

By default, IPv6 BGP specifies the
local router as the next hop for routes

sent to an IPv6 EBGP peer or peer

group, but does not change the next
hop for routes sent to an IPv6 IBGP

peer or peer group.
The IPv6 BGP-VPN instance view does

not support this command.

Configuring the MED attribute

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view.

bgp as-number

N/A