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interface GigabitEthernet0
ip address 10.1.1.254 255.255.255.0
interface GigabitEthernet1
ip address 172.16.12.254 255.255.255.0
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router bgp 1001
network 10.1.1.0 mask 255.255.255.0
neighbor 172.16.12.253 remote-as 1002
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interface GigabitEthernet0
ip address 10.1.2.254 255.255.255.0
interface GigabitEthernet1
ip address 172.16.12.253 255.255.255.0
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router bgp 1002
network 10.1.2.0 mask 255.255.255.0
neighbor 172.16.12.254 remote-as 1001
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RT1#sh ip route
C 10.1.1.0/24 is directly connected, GigabitEthernet0
B 10.1.2.0/24 [20/0] via 172.16.12.253, 00:52:50
C 172.16.12.0/24 is directly connected, GigabitEthernet1
¡Ê£´¡ËRT1¤Îneighbor¾ðÊó
RT1#sh ip bgp neighbors
BGP neighbor is 172.16.12.253, remote AS 1002, external link
BGP version 4, remote router ID 172.16.23.254
BGP state = Established, up for 01:29:06¡¡
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RT1#sh ip bgp
Network Next Hop Metric LocPrf Weight Path
*> 10.1.1.0/24 0.0.0.0 0 32768 i
*> 10.1.2.0/24 172.16.12.253 0 0 1002 i
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1)AS1¤«¤é¥ë¡¼¥Æ¥£¥ó¥°¾ðÊó¤òȯ¿®
¡¡¡¡[1.1.1.0/16][ASÈÖ¹æ 1]
2)AS2¤ò·Ðͳ¤·¤ÆÅ¾Á÷
¡¡¡¡[1.1.1.0/16][ASÈÖ¹æ 1] [ASÈÖ¹æ 2]
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¡¡¡¡[1.1.1.0/16][ASÈÖ¹æ 1] [ASÈÖ¹æ 2] [ASÈÖ¹æ 3]
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RT4#sh ip route
B 10.1.1.0/24 [20/0] via 172.16.14.254, 00:08:40
B 10.1.2.0/24 [20/0] via 172.16.14.254, 00:04:16
B 10.1.3.0/24 [20/0] via 172.16.34.254, 00:07:23
·ÐÏ©¾ðÊó¤È¤·¤Æ¤Ï¡¢ºÇû¥ë¡¼¥È¤ÎRT1¤Ë¸þ¤«¤¦·ÐÏ©¤À¤±¤¬É½¼¨¤µ¤ì¤Þ¤¹¡£¤â¤Á¤í¤ó¡¢RT1¤ÈRT4¤Î¥±¡¼¥Ö¥ë¤¬ÃÇÀþ¤¹¤ì¤Ð¡¢¤â¤¦°ìÊý¤Î¥ë¡¼¥È¤¬É⤫¤Ó¾å¤¬¤ê¤Þ¤¹¡£
Q.RT4¤«¤é¸«¤Æ¡¢10.1.1.0/24¤Î¥Í¥Ã¥È¥ï¡¼¥¯¤Î¥Ñ¥¹¤Ï2¤Ä¤¢¤ë¡£AS_PATH¾ðÊó¤Ï¤É¤¦¤Ê¤ë¤«¡£¤½¤ì¤¾¤ìµºÜ¤»¤è¡£
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RT4#sh ip bgp
Network Next Hop Metric LocPrf Weight Path
* 10.1.1.0/24 172.16.34.254 0 1003 1002 1001 i
*> 172.16.14.254 0 0 1001 i
* 10.1.2.0/24 172.16.34.254 0 1003 1002 i
*> 172.16.14.254 0 1001 1002 i
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