I am in the starting process of learning BGP. I have a lab setup right now
with 3 routers. I am trying to do a simple configuration of two routers in
the same AS and a third router connecting from a different AS.

Router A & B are in the same AS (1000).
Router A & B are using EIGRP to exchange routes between each other within
the AS
Router C has a serial Connection to Router A and is using BGP with an AS of
65000.

Router C (65000) ->Router A(1000) ->Router B(1000)

I am unable to ping Router C's ethernet address from Router B. Looking at
the routing tables on router B, router C's ethernet block is not listed in
the table?

1.) Since Router C connects to Router A using BGP and I am advertising thier
ethernet block through BGP shouldn't their block be automatically advertised
through BGP to Router B?

Here is the BGP and EIGRP portion Of The Router

ROUTER A
router eigrp 1000
network 12.0.0.0
auto-summary
no eigrp log-neighbor-changes
!
router bgp 1000
bgp log-neighbor-changes
network 12.0.0.128 mask 255.255.255.252
neighbor 12.0.0.2 remote-as 1000
neighbor 12.0.0.130 remote-as 65000

Router B
router eigrp 1000
network 12.0.0.0
auto-summary
no eigrp log-neighbor-changes
!
router bgp 1000
bgp log-neighbor-changes
neighbor 12.0.0.1 remote-as 1000

Router C
router bgp 65000
bgp log-neighbor-changes
network 12.1.1.0 mask 255.255.255.0
neighbor 12.0.0.129 remote-as 1000

Thanks
Amy

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Just a guess because I'm certainly not a BGP expert.

Assuming on router C that 12.1.1.0 is your Ethernet network, I would guess that
because you are not advertising your serial interface with a network command, it
will not work. Or maybe try "no synchronization"?

Does the network show up in the BGP table or router A or B?

"Amy l." wrote:

> I am in the starting process of learning BGP. I have a lab setup right now
> with 3 routers. I am trying to do a simple configuration of two routers in
> the same AS and a third router connecting from a different AS.
>
> Router A & B are in the same AS (1000).
> Router A & B are using EIGRP to exchange routes between each other within
> the AS
> Router C has a serial Connection to Router A and is using BGP with an AS of
> 65000.
>
> Router C (65000) ->Router A(1000) ->Router B(1000)
>
> I am unable to ping Router C's ethernet address from Router B. Looking at
> the routing tables on router B, router C's ethernet block is not listed in
> the table?
>
> 1.) Since Router C connects to Router A using BGP and I am advertising thier
> ethernet block through BGP shouldn't their block be automatically advertised
> through BGP to Router B?
>
> Here is the BGP and EIGRP portion Of The Router
>
> ROUTER A
> router eigrp 1000
> network 12.0.0.0
> auto-summary
> no eigrp log-neighbor-changes
> !
> router bgp 1000
> bgp log-neighbor-changes
> network 12.0.0.128 mask 255.255.255.252
> neighbor 12.0.0.2 remote-as 1000
> neighbor 12.0.0.130 remote-as 65000
>
> Router B
> router eigrp 1000
> network 12.0.0.0
> auto-summary
> no eigrp log-neighbor-changes
> !
> router bgp 1000
> bgp log-neighbor-changes
> neighbor 12.0.0.1 remote-as 1000
>
> Router C
> router bgp 65000
> bgp log-neighbor-changes
> network 12.1.1.0 mask 255.255.255.0
> neighbor 12.0.0.129 remote-as 1000
>
> Thanks
> Amy

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