bgp路由汇聚

 IBGP环回建邻

bgp 100
 router-id 1.1.1.1
 peer 4.4.4.4 as-number 100 
 peer 4.4.4.4 connect-interface LoopBack0

EBGP直连建邻

bgp 100
 router-id 4.4.4.4
 peer 5.5.5.5 as-number 101 
 peer 5.5.5.5 ebgp-max-hop 255 

as100到as101只能有汇总通过

逐条宣告所有的明细路由，再进行标准的BGP聚合配置

  network 1.1.1.1 255.255.255.255 
  network 2.2.2.2 255.255.255.255 
  network 3.3.3.3 255.255.255.255 
  network 4.4.4.4 255.255.255.255 
  network 45.1.1.0 255.255.255.0 
  network 172.16.0.0 255.255.255.252 
  network 172.16.0.4 255.255.255.252 
  network 172.16.0.8 255.255.255.252 
  network 172.16.0.10 255.255.255.255 
  network 172.16.0.11 255.255.255.255 
  network 172.16.0.12 255.255.255.252 
  network 172.16.0.16 255.255.255.252 
  network 172.16.0.20 255.255.255.252 
  network 172.16.0.24 255.255.255.252 
  network 172.16.0.25 255.255.255.255 
  network 172.16.0.27 255.255.255.255 
  aggregate 172.16.0.0 255.255.0.0 detail-suppressed 

 as101到as100除了汇总还有r8的两个环回通过，也是在r5上先逐条宣告明细路由，然后进行流量控制

[R5]ip ip-prefix xx permit 8.8.8.8 32
[R5]ip ip-prefix xx permit 192.168.0.25 32
[R5]route-policy yy deny node  10
Info: New Sequence of this List.
[R5-route-policy]if-match ip-prefix xx
[R5-route-policy]q
[R5]route-policy yy permit node 20
[R5]bgp 101
[R5-bgp]aggregate 192.168.0.0 24 detail-suppressed su	
[R5-bgp]aggregate 192.168.0.0 24 detail-suppressed suppress-policy yy
[R5-bgp]q