Nested Route Reflection Cluster

Figure 1.1

R1

router bgp 65000
 bgp cluster-id 10
 neighbor 2.2.2.2 remote-as 65000
 neighbor 2.2.2.2 update-source Loopback0
 neighbor 2.2.2.2 route-reflector-client
 neighbor 3.3.3.3 remote-as 65000
 neighbor 3.3.3.3 update-source Loopback0
 neighbor 3.3.3.3 route-reflector-client

R2

router bgp 65000
 bgp cluster-id 20
 net 22.22.22.0 mask 255.255.255.0
 neighbor 1.1.1.1 remote-as 65000
 neighbor 1.1.1.1 update-source Loopback0
 neighbor 4.4.4.4 remote-as 65000
 neighbor 4.4.4.4 update-source Loopback0
 neighbor 4.4.4.4 route-reflector-client

R3

router bgp 65000
 bgp cluster-id 30
 net 33.33.33.0 mask 255.255.255.0
 neighbor 1.1.1.1 remote-as 65000
 neighbor 1.1.1.1 update-source Loopback0
 neighbor 5.5.5.5 remote-as 65000
 neighbor 5.5.5.5 update-source Loopback0
 neighbor 5.5.5.5 route-reflector-client

R4

router bgp 65000
 network 44.44.44.0 mask 255.255.255.0
 neighbor 2.2.2.2 remote-as 65000
 neighbor 2.2.2.2 update-source Loopback0

R5

router bgp 65000
 network 55.55.55.0 mask 255.255.255.0
 neighbor 3.3.3.3 remote-as 65000
 neighbor 3.3.3.3 update-source Loopback0

Verify the bgp at edges router.

R4#sh ip bgp summary
BGP router identifier 44.44.44.44, local AS number 65000
BGP table version is 5, main routing table version 5
4 network entries using 468 bytes of memory
4 path entries using 208 bytes of memory
3/2 BGP path/bestpath attribute entries using 372 bytes of memory
2 BGP rrinfo entries using 64 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 1112 total bytes of memory
BGP activity 4/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
2.2.2.2         4    65000      16      14           5        0       0  00:09:01        3

R5#sh ip bgp summary
BGP router identifier 55.55.55.55, local AS number 65000
BGP table version is 5, main routing table version 5
4 network entries using 468 bytes of memory
4 path entries using 208 bytes of memory
3/2 BGP path/bestpath attribute entries using 372 bytes of memory
2 BGP rrinfo entries using 64 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 1112 total bytes of memory
BGP activity 4/0 prefixes, 4/0 paths, scan interval 60 secs

Neighbor        V    AS      MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
3.3.3.3           4    65000      14      12              5        0    0      00:07:22        3

R4#sh ip bgp
BGP table version is 5, local router ID is 44.44.44.44
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i22.22.22.0/24    2.2.2.2                  0    100      0 i
*>i33.33.33.0/24    3.3.3.3                  0    100      0 i
*> 44.44.44.0/24    0.0.0.0                  0         32768 i
*>i55.55.55.0/24    5.5.5.5                  0    100      0 i

R5#sh ip bgp
BGP table version is 5, local router ID is 55.55.55.55
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i22.22.22.0/24    2.2.2.2                  0    100      0 i
*>i33.33.33.0/24    3.3.3.3                  0    100      0 i
*>i44.44.44.0/24    4.4.4.4                  0    100      0 i
*> 55.55.55.0/24    0.0.0.0                  0         32768 i

R4#sh ip bgp 55.55.55.0
BGP routing table entry for 55.55.55.0/24, version 5
Paths: (1 available, best #1, table Default-IP-Routing-Table)
  Not advertised to any peer
  Local
    5.5.5.5 (metric 5) from 2.2.2.2 (2.2.2.2)
      Origin IGP, metric 0, localpref 100, valid, internal, best
      Originator: 55.55.55.55, Cluster list: 0.0.0.20, 0.0.0.10, 0.0.0.30

R5#sh ip bgp 44.44.44.0
BGP routing table entry for 44.44.44.0/24, version 5
Paths: (1 available, best #1, table Default-IP-Routing-Table)
  Not advertised to any peer
  Local
    4.4.4.4 (metric 5) from 3.3.3.3 (3.3.3.3)
      Origin IGP, metric 0, localpref 100, valid, internal, best
      Originator: 44.44.44.44, Cluster list: 0.0.0.30, 0.0.0.10, 0.0.0.20

More clear you can verify from R1.

R1#sh ip bgp 44.44.44.0
BGP routing table entry for 44.44.44.0/24, version 3
Paths: (1 available, best #1, table Default-IP-Routing-Table)
  Advertised to update-groups:
     1        
  Local, (Received from a RR-client)
    4.4.4.4 (metric 3) from 2.2.2.2 (2.2.2.2)
      Origin IGP, metric 0, localpref 100, valid, internal, best
      Originator: 44.44.44.44, Cluster list: 0.0.0.20

R1#sh ip bgp 55.55.55.0
BGP routing table entry for 55.55.55.0/24, version 5
Paths: (1 available, best #1, table Default-IP-Routing-Table)
  Advertised to update-groups:
     1        
  Local, (Received from a RR-client)
    5.5.5.5 (metric 3) from 3.3.3.3 (3.3.3.3)
      Origin IGP, metric 0, localpref 100, valid, internal, best
      Originator: 55.55.55.55, Cluster list: 0.0.0.30