BGP configuration

[Glloq007]

Hello,

I have a problem with BGP configuration.
Provider annonunce me a default gateway towards BGP.
My router is connected to my provider at 2 different POP through 2 serial links.
I see the announcement of the default gateway, but it is not be in my routing table.
That means that for the moment, I have to setup a static route.

Thanks if someone could help me.

Serge

 

[leedsit]

Hi,

could you run

show ip bgp

on your router and post the output?

LEEroy
MCNE6,CCNP,CWNA,CCSA,Project+

 

[Glloq007]

Hi,

Find here below the result of show command.

euresa#sh ip bgp
BGP table version is 3, local router ID is 194.154.202.29
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path
*> 0.0.0.0 195.46.243.173 0 65000 i
*> 194.154.202.16/28
0.0.0.0 0 32768 i
euresa#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is 0.0.0.0 to network 0.0.0.0

195.46.243.0/30 is subnetted, 2 subnets
C 195.46.243.172 is directly connected, Serial0/1
C 195.46.243.168 is directly connected, Serial0/0
194.154.202.0/24 is variably subnetted, 4 subnets, 3 masks
S 194.154.202.16/29 [1/0] via 194.154.202.30
S 194.154.202.16/28 is directly connected, Null0
S 194.154.202.24/30 [1/0] via 194.154.202.30
C 194.154.202.28/30 is directly connected, Ethernet0/0
S* 0.0.0.0/0 is directly connected, Serial0/1
euresa#

 

[leedsit]

Hi,

Well it seems bgp does know about that route, however your static with an Admin distance of 1 is superceding the BGP Route with a higher admin distance.

You need to remove the static route to allow the BGP route in.... If this is a live enviroment you could make the static entry have a higher admin distance just incase the BGP route does not populate.

try either of the following

1) remove your static route
or add
2) Ip route 0.0.0.0 0.0.0.0 serial 0/1 240



LEEroy
MCNE6,CCNP,CWNA,CCSA,Project+

 

[Glloq007]

Hi,

Thank for your help and cooperation.
I thought already having tested this configuration without success. I'm not sure, because I'm not in front of the router.
Could you have a look to the script below, and give me your appreciation.

interface Serial0/0
description LL towards P&T Luxembourg-Gare X.21
bandwidth 2048
ip address 195.46.243.170 255.255.255.252
no ip redirects
no ip mroute-cache
!
interface Serial0/1
description LL towards P&T Esch V.35
bandwidth 2048
ip address 195.46.243.174 255.255.255.252
no ip redirects
no ip mroute-cache
!
router bgp 65017
no synchronization
bgp router-id 194.154.202.29
bgp always-compare-med
bgp cluster-id 3264924188
bgp log-neighbor-changes
bgp deterministic-med
network 194.154.202.16 mask 255.255.255.240
neighbor bgp-customer peer-group
neighbor bgp-customer ebgp-multihop 5
neighbor bgp-customer next-hop-self
neighbor bgp-customer soft-reconfiguration inbound
neighbor bgp-customer prefix-list bogus in
neighbor 195.46.243.169 remote-as 65000
neighbor 195.46.243.169 peer-group bgp-customer
neighbor 195.46.243.169 description P&T Luxembourg-GARE
no neighbor 195.46.243.169 prefix-list bogus in
neighbor 195.46.243.173 remote-as 65000
neighbor 195.46.243.173 peer-group bgp-customer
neighbor 195.46.243.173 description P&T Luxembourg-GARE
no neighbor 195.46.243.173 prefix-list bogus in
no auto-summary
!
ip classless
ip default-network 0.0.0.0
ip route 0.0.0.0 0.0.0.0 Serial0/0 255
ip route 0.0.0.0 0.0.0.0 Serial0/1
ip route 194.154.202.16 255.255.255.240 Null0
ip route 194.154.202.16 255.255.255.248 194.154.202.30
ip route 194.154.202.24 255.255.255.252 194.154.202.30
no ip http server
!
!
ip prefix-list AS6500-P&T seq 5 permit 195.154.202.16/28
ip prefix-list AS6500-P&T seq 10 permit 0.0.0.0/32
!
ip prefix-list bogus description denies bogus networks
ip prefix-list bogus seq 5 deny 192.168.0.0/16 le 32
ip prefix-list bogus seq 10 deny 10.0.0.0/8 le 32
ip prefix-list bogus seq 15 deny 172.16.0.0/12 le 32
ip prefix-list bogus seq 20 deny 127.0.0.0/8 le 32
ip prefix-list bogus seq 25 permit 0.0.0.0/0 le 32

 

[plshlpme]

can you show us the ip bgp without the static route?
in your config i see you have two static routes.
youll need to assign a higher cost to both of those.
currently if you receive a default route via bgp on your s0/0... then the static route that you have assigned for the s0/1 will win over it because the admin distance is much lower.