R0106-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V7)

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To disable BGP from considering AS_PATH during optimal route selection (IPv6 unicast/multicast
address family):
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP IPv6 unicast address
family view, BGP-VPN IPv6
unicast address family view, or
BGP IPv6 multicast address
family view.
• Enter BGP IPv6 unicast address
family view:
a. bgp as-number
b. address-family ipv6
[ unicast ]
• Enter BGP-VPN IPv6 unicast
address family view:
c. bgp as-number
d. ip vpn-instance
vpn-instance-name
e. address-family ipv6
[ unicast ]
• Enter BGP IPv6 multicast
address family view:
f. bgp as-number
g. address-family ipv6
multicast
N/A
3. Disable BGP from considering
AS_PATH during optimal route
selection.
bestroute as-path-neglect
By default, BGP considers
AS_PATH during optimal route
selection.
Advertising a fake AS number to a peer or peer group
After you move a BGP router from an AS to another AS (from AS 2 to AS 3 for example), you have to
modify the AS number of the router on all its EBGP peers. To avoid such modifications, you can configure
the router to advertise a fake AS number 2 to its EBGP peers so that the EBGP peers still think that Router
A is in AS 2.
To advertise a fake AS number to a peer or peer group (IPv4 unicast/multicast address family):
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view or BGP-VPN
instance view.
• Enter BGP view:
bgp as-number
• Enter BGP-VPN instance view:
a. bgp as-number
b. ip vpn-instance
vpn-instance-name
N/A
3. Advertise a fake AS number to
a peer or peer group.
peer { group-name | ip-address }
fake-as as-number
By default, no fake AS number is
advertised to a peer or peer group.
This command applies to only
EBGP peers or EBGP peer groups.
To advertise a fake AS number to a peer or peer group (IPv6 unicast/multicast address family):