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[RouterD-bgp-ipv4] peer 194.1.1.2 enable
[RouterD-bgp-ipv4] peer 195.1.1.2 enable
[RouterD-bgp-ipv4] quit
[RouterD-bgp] quit
4.
Configure different attribute values for the route 1.0.0.0/8 to make Router D give priority to the
route learned from Router C:
{
(Method 1.) Specify a higher MED value for the route 1.0.0.0/8 advertised to 192.1.1.2 to make
Router D give priority to the route learned from Router C:
# Define ACL 2000 to permit the route 1.0.0.0/8.
[RouterA] acl number 2000
[RouterA-acl-basic-2000] rule permit source 1.0.0.0 0.255.255.255
[RouterA-acl-basic-2000] quit
# Define routing policy
apply_med_50
that sets the MED value of route 1.0.0.0/8 to 50, and
routing policy
apply_med_100
that sets the MED value of route 1.0.0.0/8 to 100.
[RouterA] route-policy apply_med_50 permit node 10
[RouterA-route-policy-apply_med_50-10] if-match ip address acl 2000
[RouterA-route-policy-apply_med_50-10] apply cost 50
[RouterA-route-policy-apply_med_50-10] quit
[RouterA] route-policy apply_med_100 permit node 10
[RouterA-route-policy-apply_med_100-10] if-match ip address acl 2000
[RouterA-route-policy-apply_med_100-10] apply cost 100
[RouterA-route-policy-apply_med_100-10] quit
# Apply routing policy
apply_med_50
to the route advertised to 193.1.1.2 (Router C), and
apply routing policy
apply_med_100
to the route advertised to 192.1.1.2 (Router B).
[RouterA] bgp 100
[RouterA-bgp] address-family ipv4 unicast
[RouterA-bgp-ipv4] peer 193.1.1.2 route-policy apply_med_50 export
[RouterA-bgp-ipv4] peer 192.1.1.2 route-policy apply_med_100 export
[RouterA-bgp-ipv4] quit
[RouterA-bgp] quit
# Display the BGP routing table on Router D.
[RouterD] display bgp routing-table ipv4
Total number of routes: 2
BGP local router ID is 195.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* >i 1.0.0.0 193.1.1.1 50 100 0 100i
* i 192.1.1.1 100 100 0 100i
The route 1.0.0.0/8 learned from Router C is the optimal route.
{
(Method 2.) Specify different local preferences for route 1.0.0.0/8 on Router B and C to make
Router D give priority to the route learned from Router C.