Configuration procedure

Procedure
  1. Configure IP addresses for interfaces (omitted.)
  2. Configure eBGP.
  3. # Configure Switch A. 
    switch(config)# router bgp 10
switch(bgp)# bgp router-id 1.1.1.1
switch(bgp)# neighbor 200.1.2.2 remote-as 20
switch(bgp)# network 9.1.1.0/255.255.255.0/8
switch(bgp)# exit
  4. # Configure Switch B. 
     
switch(config)# bgp 20
switch(bgp)# bgp router-id 2.2.2.2
switch(bgp)# neighbor 200.1.2.1 remote-as 10
switch(bgp)# neighbor 200.1.3.2 remote-as 30
switch(bgp)# exit
  5. # Configure Switch C. 
    switch(config)# bgp 30
switch(bgp)# bgp router-id 3.3.3.3
switch(bgp)# neighbor 200.1.3.1 remote-as 20
switch(bgp)# exit
  6. # Display the BGP routing table on Switch B. 
    switch(config)# show ip bgp 9.1.1.0

Local AS : 20 Local Router-id : 2.2.2.2
BGP Table Version  : 3

Network : 9.1.1.0/24       Nexthop         : 200.1.2.1
Peer   : 200.1.2.1        Origin          : igp 
Metric : 0                Local Pref      : 
Weight : 0                Calc. Local Pref : 100
Valid  : Yes              Type            : external
Stale  : No
Best   : Yes (Only Route Available) 
AS-Path : 100
Communities :
  7. Switch B advertised routes to Switch C in AS 30.
  8. # Display the routing table on Switch C. 
    switch(config)# show ip bgp

Local AS : 30
Local Router-id : 3.3.3.3

BGP Table Version  : 1
Status codes: * - valid, > - best, i - internal, e - external, s - stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network        Nexthop   Metric LocalPref Weight AsPath
-------------------------------------------------------
*>i 9.1.1.0/24 200.1.3.1      0            100     10i
  9. Switch C learned route 9.1.1.0/24 from Switch B.
  10. Configure the BGP community.
  11. # Configure a routing policy. 
    route-map bgp-out permit seq 10
switch(route-map-bgp-out)# set community no-export
switch(route-map-bgp-out)# exit
  12. # Apply the routing policy. 
    switch(config)# bgp 10
switch(bgp)# neighbor 200.1.2.2 route-map bgp-out out
  13. # Display the route on Switch B. 
    switch(config)# show ip bgp 9.1.1.0/24

Local AS : 20 Local Router-id : 2.2.2.2
BGP Table Version  : 3

Network     : 9.1.1.0/24   Nexthop         : 200.1.2.1
Peer       : 200.1.2.1    Origin          : igp Metric     : 0            Local Pref      : Weight  
   : 0            Calc. Local Pref : 100
Valid      : Yes          Type            : external
Stale      : No
Best       : Yes (Only Route Available) AS-Path    : 100
Communities: no-export

# Display the routing table on Switch C.
switch# show ip bgp 9.1.1.0/24
  14. The route 9.1.1.0/24 is not available in the routing table of Switch C.