374
[SwitchD] ip as-path 1 permit .*200.*
# Create routing policy
rt1
with node 1, and specify the match mode as
deny
to deny routes from
AS 200.
[SwitchD] route-policy rt1 deny node 1
[SwitchD-route-policy] if-match as-path 1
[SwitchD-route-policy] quit
# Create routing policy
rt1
with node 10, and specify the match mode as
permit
to permit routes
from other ASs.
[SwitchD] route-policy rt1 permit node 10
[SwitchD-route-policy] quit
# On Switch D, specify routing policy
rt1
to filter routes received from peer 1.1.3.1.
[SwitchD] bgp 400
[SwitchD-bgp] peer 1.1.3.1 route-policy rt1 import
# Display the BGP routing table information of Switch D.
[SwitchD-bgp] display bgp routing-table
Total Number of Routes: 3
BGP Local router ID is 4.4.4.4
Status codes: * - valid, > - best, d - damped,
h - history, i - internal, s - suppressed, S - Stale
Origin : i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
*> 4.4.4.0/24 1.1.3.1 0 300 100i
*> 5.5.5.0/24 1.1.3.1 0 300 100i
*> 6.6.6.0/24 1.1.3.1 0 300 100i
The output shows that Switch D has learned only routes 4.4.4.0/24, 5.5.5.0/24, and
6.6.6.0/24 from AS 100.
Troubleshooting routing policy configuration
IPv4 routing information filtering failure
Symptom
The routing protocol is running properly, but filtering routing information failed.
Analysis
At least one item of the IP prefix list must be configured as permit mode, and at least one node in the
routing policy must be configured as permit mode.
Solution
1.
Use the
display ip ip-prefix
command to display IP prefix list information.
2.
Use the
display route-policy
command to display routing policy information.
