Configuring the med attribute, Configuring the as_path attribute – H3C Technologies H3C S10500 Series Switches User Manual

Page 347

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NOTE:

To ensure an iBGP peer can find the correct next hop, 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.

Configuring the MED attribute

Follow these steps to configure the MED attribute:

To do…

Use the command…

Remarks

Enter system view

system-view

Enter BGP view

bgp as-number

Enter IPv6 address family view

ipv6-family

Configure a default MED value

default med med-value

Optional
Defaults to 0

Enable the comparison of MED for
routes from different eBGP peers

compare-different-as-med

Optional
Not enabled by default.

Enable the comparison of MED for
routes from each AS

bestroute compare-med

Optional
Disabled by default

Enable the comparison of MED for
routes from confederation peers

bestroute med-confederation

Optional
Disabled by default

Configuring the AS_PATH attribute

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 IPv6 address family view

ipv6-family

Allow the local AS number to

appear in AS_PATH of routes from
a peer or peer group and specify

the repeat times

peer { ipv6-group-name |

ipv6-address } allow-as-loop
[ number ]

Optional
Not allowed by default

Specify a fake AS number for an
IPv6 peer or peer group

peer { ipv6-group-name |
ipv6-address } fake-as as-number

Optional
Not specified by default.

Disable IPv6 BGP from considering
the AS_PATH during best route
selection

bestroute as-path-neglect

Optional
Enabled by default.

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