From: folivore (folivore@hotmail.com)
Date: Fri Apr 18 2003 - 02:10:31 GMT-3
EBGP has a lower distance than RIP,
so please use backdoor command on R6
such as " network 198.5.51.0 backdoor ".....
Or manually change the distance of either RIP or BGP.
----- Original Message -----
From: "DougAtHome" <dcalton@fuse.net>
To: <huntl@webcentral.com.au>; "ccielab" <ccielab@groupstudy.com>
Sent: Thursday, April 17, 2003 6:58 AM
Subject: Re: BGP problem
> I had similar problems last week. After I turned on debug ip routing, I
> would see that routing installed the RIP entry in the routing table first,
> while BGP was futzing around with establishing neighbor sessions. When
BGP
> came up, the route was replaced by BGP. Then, as you said, after 5
minutes,
> it went to possibly down. My theory was and still is that the table is a
> bit "poluted" and, although it knows that it is no longer an RIP route, it
> still looks for RIP updates which never arrive. Since it was a lab
> situation, I filtered out the redundant loops from RIP, allowing BGP to be
> the sole source of these updates. I still suspect an IOS bug here, but
> since I make my first attempt for the R&S Lab on the 27th, who has time to
> research this one?
>
>
>
> -----Original Message-----
> From: Hunt Lee [mailto:huntl@webcentral.com.au]
> Sent: Wednesday, April 16, 2003 9:12 PM
> To: 'ccielab@groupstudy.com'
> Subject: BGP problem
>
>
> Hi Group,
>
>
> ... - r6 --- r13 - Loopback 0 (198.5.51.1/24)
> - Loopback 1 (198.5.52.1/24)
> - Loopback 2 (198.5.53.1/24)
> - Loopback 0 (198.5.54.1/24)
>
> The link between the routers are EBGP, and they are also talking in RIPv1.
>
> ...and there are some OSPF routers on the left of r6. And r6 is part of a
> BGP confederation with the routers on the left.
>
> r13's interface (to r6) - 200.100.100.13 /24
>
> All 4 loopbacks are advertised by RIPv1 as well as BGP.
>
> Ok. What I don't understand is that when r6 first boots up, it can see
the
> 4 BGP routes fine, & can ping fine also...
>
> r6#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, 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 not set
>
> C 200.100.100.0/24 is directly connected, Ethernet0
> R 172.16.0.0/16 [120/2] via 200.100.100.13, 00:00:05, Ethernet0
> B 198.5.51.0/24 [20/0] via 200.100.100.13, 00:01:27
> B 198.5.53.0/24 [20/0] via 200.100.100.13, 00:01:27
> B 198.6.53.0/24 [200/0] via 150.10.2.2, 00:00:57
> B 198.5.52.0/24 [20/0] via 200.100.100.13, 00:01:27
> B 198.5.54.0/24 [20/0] via 200.100.100.13, 00:01:27
> 150.10.0.0/16 is variably subnetted, 13 subnets, 5 masks
> O IA 150.10.20.0/25 [110/129] via 150.10.60.5, 00:00:05, Serial0
> O IA 150.10.10.0/28 [110/128] via 150.10.60.5, 00:00:05, Serial0
> O E2 150.10.4.0/24 [110/20] via 150.10.60.5, 00:00:05, Serial0
> C 150.10.6.0/24 is directly connected, Loopback0
> O IA 150.10.5.5/32 [110/65] via 150.10.60.5, 00:00:05, Serial0
> O IA 150.10.2.2/32 [110/129] via 150.10.60.5, 00:00:05, Serial0
> O IA 150.10.1.1/32 [110/129] via 150.10.60.5, 00:00:05, Serial0
> O E2 150.10.3.0/24 [110/20] via 150.10.60.5, 00:00:05, Serial0
> C 150.10.60.0/24 is directly connected, Serial0
> O IA 150.10.50.0/24 [110/128] via 150.10.60.5, 00:00:05, Serial0
> O E2 150.10.45.0/24 [110/20] via 150.10.60.5, 00:00:05, Serial0
> O E2 150.10.40.0/24 [110/20] via 150.10.60.5, 00:00:05, Serial0
> C 150.10.65.0/30 is directly connected, BRI0
> B 198.6.48.0/21 [200/0] via 150.10.2.2, 00:00:59
> r6#
>
>
> r6#ping 198.5.51.1
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 198.5.51.1, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms
> r6#ping 198.5.52.1
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 198.5.52.1, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms
> r6#ping 198.5.53.1
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 198.5.53.1, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 1/3/4 ms
> r6#ping 198.5.54.1
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 198.5.54.1, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms
> r6#
>
>
> r6#sh ip bgp
> BGP table version is 11, local router ID is 150.10.6.6
> 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
> *> 150.10.3.0/24 150.10.10.3 50 100 0 (250) i
> *> 150.10.20.0/25 150.10.10.3 100 100 0 (250) i
> *> 150.10.45.0/24 150.10.40.4 100 100 0 (250) i
> *> 150.10.50.0/24 150.10.5.5 50 100 0 (250) i
> *> 198.5.51.0 200.100.100.13 0 1000 130 i
> *> 198.5.52.0 200.100.100.13 0 1000 130 i
> *> 198.5.53.0 200.100.100.13 0 1000 130 i
> *> 198.5.54.0 200.100.100.13 0 1000 130 i
> *> 198.6.48.0/21 150.10.2.2 100 0 (250 8) i
> *> 198.6.53.0 150.10.2.2 0 100 0 (250 8) 1000
i
> r6#
>
> But if you wait for around 3 mins, those 4 routes would say "...is
possibly
> down", which I have never seen on a BGP route before (a BGP route is
> normally either there or not there, rather than saying "is possibly down".
>
> r6#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, 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 not set
>
> C 200.100.100.0/24 is directly connected, Ethernet0
> R 172.16.0.0/16 [120/2] via 200.100.100.13, 00:00:02, Ethernet0
> B 198.5.51.0/24 is possibly down, routing via 200.100.100.13
> B 198.5.53.0/24 is possibly down, routing via 200.100.100.13
> B 198.6.53.0/24 [200/0] via 150.10.2.2, 00:05:54
> B 198.5.52.0/24 is possibly down, routing via 200.100.100.13
> B 198.5.54.0/24 is possibly down, routing via 200.100.100.13
> 150.10.0.0/16 is variably subnetted, 13 subnets, 5 masks
> O IA 150.10.20.0/25 [110/129] via 150.10.60.5, 00:05:02, Serial0
> O IA 150.10.10.0/28 [110/128] via 150.10.60.5, 00:05:02, Serial0
> O E2 150.10.4.0/24 [110/20] via 150.10.60.5, 00:05:02, Serial0
> C 150.10.6.0/24 is directly connected, Loopback0
> O IA 150.10.5.5/32 [110/65] via 150.10.60.5, 00:05:02, Serial0
> O IA 150.10.2.2/32 [110/129] via 150.10.60.5, 00:05:03, Serial0
> O IA 150.10.1.1/32 [110/129] via 150.10.60.5, 00:05:03, Serial0
> O E2 150.10.3.0/24 [110/20] via 150.10.60.5, 00:05:03, Serial0
> C 150.10.60.0/24 is directly connected, Serial0
> O IA 150.10.50.0/24 [110/128] via 150.10.60.5, 00:05:03, Serial0
> O E2 150.10.45.0/24 [110/20] via 150.10.60.5, 00:05:03, Serial0
> O E2 150.10.40.0/24 [110/20] via 150.10.60.5, 00:05:03, Serial0
> C 150.10.65.0/30 is directly connected, BRI0
> B 198.6.48.0/21 [200/0] via 150.10.2.2, 00:05:56
> r6#
>
>
> r6#sh ip bgp
> BGP table version is 11, local router ID is 150.10.6.6
> 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
> *> 150.10.3.0/24 150.10.10.3 50 100 0 (250) i
> *> 150.10.20.0/25 150.10.10.3 100 100 0 (250) i
> *> 150.10.45.0/24 150.10.40.4 100 100 0 (250) i
> *> 150.10.50.0/24 150.10.5.5 50 100 0 (250) i
> *> 198.5.51.0 200.100.100.13 0 1000 130 i
> *> 198.5.52.0 200.100.100.13 0 1000 130 i
> *> 198.5.53.0 200.100.100.13 0 1000 130 i
> *> 198.5.54.0 200.100.100.13 0 1000 130 i
> *> 198.6.48.0/21 150.10.2.2 100 0 (250 8) i
> *> 198.6.53.0 150.10.2.2 0 100 0 (250 8) 1000
i
> r6#
>
>
> r6#ping 198.5.51.1
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 198.5.51.1, timeout is 2 seconds:
> .....
> Success rate is 0 percent (0/5)
> r6#sh ip route 198.5.51.1
> Routing entry for 198.5.51.0/24
> Known via "bgp 6", distance 20, metric 4294967295 (inaccessible)
> Tag 130, type external
> Last update from 200.100.100.13 00:04:10 ago
> Hold down timer expires in 120 secs
>
> r6#
>
>
> Does this have anything to do with RIPv1 + BGP using together?
>
> Anyway, here are the configs for the 2 routers ;)
>
> For r6:-
>
> interface Ethernet0
> ip address 200.100.100.6 255.255.255.0
> ip pim sparse-mode
>
> router ospf 1
> log-adjacency-changes
> area 5 authentication message-digest
> redistribute rip metric 65 metric-type 1 subnets route-map Even
> network 150.10.6.6 0.0.0.0 area 5
> network 150.10.60.6 0.0.0.0 area 5
> network 150.10.65.2 0.0.0.0 area 5
> !
> router rip
> redistribute ospf 1 metric 2
> passive-interface BRI0
> network 200.100.100.0
>
> router bgp 6
> no synchronization
> bgp log-neighbor-changes
> bgp confederation identifier 22
> bgp confederation peers 250
> neighbor 150.10.5.5 remote-as 250
> neighbor 150.10.5.5 ebgp-multihop 255
> neighbor 150.10.5.5 update-source Loopback0
> neighbor 150.10.5.5 next-hop-self
> neighbor 200.100.100.13 remote-as 130
> neighbor 200.100.100.13 route-map Weight in
> neighbor 200.100.100.13 filter-list 2 out
> no auto-summary
>
> ip as-path access-list 2 permit ^$
> ip pim rp-address 150.10.5.5
>
> route-map Weight permit 10
> set weight 1000
>
> route-map Even permit 10
> match ip address 1
>
> access-list 1 permit 198.5.0.0 0.0.254.255
> access-list 1 permit 200.0.0.0 0.255.255.255
> access-list 1 permit 172.16.0.0 0.0.255.255
> access-list 1 permit 10.0.0.0 0.255.255.255
>
> ... and for r13:-
>
> interface Loopback0
> ip address 198.5.51.1 255.255.255.0
> !
> interface Loopback1
> ip address 198.5.52.1 255.255.255.0
> !
> interface Loopback2
> ip address 198.5.53.1 255.255.255.0
> !
> interface Loopback3
> ip address 198.5.54.1 255.255.255.0
>
> interface FastEthernet0/0
> ip address 200.100.100.13 255.255.255.0
> ip pim sparse-mode
> ip igmp join-group 224.0.5.5
> speed 100
> full-duplex
>
> router rip
> redistribute static metric 2
> network 198.5.51.0
> network 198.5.52.0
> network 198.5.53.0
> network 198.5.54.0
> network 200.100.100.0
> !
> router bgp 130
> bgp log-neighbor-changes
> network 198.5.51.0
> network 198.5.52.0
> network 198.5.53.0
> network 198.5.54.0
> neighbor 200.100.100.6 remote-as 22
> no auto-summary
>
> ip route 172.16.1.0 255.255.255.0 10.1.1.14
> !
> end
>
> Any help will be greatly appreciated.
>
> Regards,
> Hunt
This archive was generated by hypermail 2.1.4 : Thu May 01 2003 - 13:35:57 GMT-3