BGP is driving me crazy.

From: Scott O'Donnell (scotto@xxxxxxxxxxxx)
Date: Tue Jul 06 1999 - 00:02:41 GMT-3

   
Hello,
I hope I can explain this.

I have setup five routers RA,RB,RC,RD,RE (left to right). All routers
are connected in a row via serial links.

Like this: RA ------ RB ------ RC ------- RD ------- RE

I have the links assigned subnets as follows:
RA->RB = 4.4.4.0/24
RB->RC = 3.3.3.0/24
RC->RD = 2.2.2.0/24
RD->RE = 1.1.1.0/24

RA is assigned and running BGP AS 400
RB,RC,RD are assigned and running BGP AS 100, IBGP connections fully
meshed.
RE is assigned and running BGP AS 200

RE is originating network 128.213.1.0/24 with a network command
"Network 128.213.0.0"
RD learns the 128.213.0.0 route and places it in it's table with the
next hop as 1.1.1.1 (RE)
RC learns the 128.213.0.0 route in it's BGP table (SHO IP BGP) but
doesn't place it in the route table.
RB learns the 128.213.0.0 route in it's BGP table (SHO IP BGP) but
continues to display a console
message "BGP: no valid path for 128.213.0.0/16" .

Both RC and RB have routes in their route table for network 1.0.0.0/8

rB#sho ip bgp
BGP table version is 39, local router ID is 200.200.200.5
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
*>i1.0.0.0 2.2.2.2 0 100 0 i
*>i2.0.0.0 2.2.2.2 0 100 0 i
*>i3.0.0.0 2.2.2.1 1 100 0 i
*> 110.0.0.0 4.4.4.4 0 0 400 i
* i128.213.0.0 1.1.1.1 0 100 0 200 i
*>i192.212.1.0 2.2.2.2 0 100 0 i

sho ip route
R 1.0.0.0/8 [120/2] via 3.3.3.3, Serial0
R 2.0.0.0/8 [120/1] via 3.3.3.3, Serial0
     3.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
S 3.0.0.0/8 is directly connected, Null0
C 3.3.3.0/24 is directly connected, Serial0
     4.0.0.0/24 is subnetted, 1 subnets
C 4.4.4.0 is directly connected, Ethernet0
B 110.0.0.0/8 [20/0] via 4.4.4.4
R 192.212.1.0/24 [120/2] via 3.3.3.3, Serial0

Why doesn't RB learn about the 128.213.0.0 network in AS 200?

Am I missing the big picture?

Scott

This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:21:41 GMT-3