1、項目案例計算機網絡系統集成項目（工程項目案例及實踐）所在系別： 計算機技術系 所屬專業： 計算機網絡技術 指導教師： 張海峰 專業負責人： 孫志成 SR8800-X BGP與BFD聯動典型配置一、功能需求某公司的兩個部門相距較遠，Device A和Device F分別作為這兩個部門的出口設備，現通過部署BGP，使兩個部門可以進行業務通信。已知Device B和Device D都支持BFD功能，公司希望使用BGP與BFD聯動技術，采用BFD控制報文方式檢測AS 200與AS 300之間通信的主鏈路狀態，實現當Device B或Device D之間的鏈路出現故障（如鏈路down）時，BFD能夠快速

2、感知并通告BGP協議。具體要求如下：在AS 100內使用OSPF作為IGP。配置Device B<>Device C<>Device D鏈路作為主鏈路，負責轉發Device A和Device F之間的流量，并采用BFD控制報文的方式檢測主鏈路。當主鏈路發生故障時，BFD能夠快速檢測并通告BGP協議，使得迅速切換到Device B<>Device E<>Device D這條路徑進行通信。二、組網信息及描述Device B和Device D都支持BFD，可以使用BFD控制報文方式，通信雙方至少要有一方運行在主動模式才能成功建立起BFD會話。為了使De

3、vice B<>Device C<>Device D成為主鏈路，需要通過路由策略配置其路由開銷低于鏈路Device B<>Device E<>Device D的路由開銷。三、配置步驟  配置各接口的IP地址(1)      配置Device A各接口的IP地址<DeviceA> system-viewDeviceA interface ten-gigabitethernet 3/0/1DeviceA-Ten-GigabitEthernet3/0/1 und

4、o shutdownDeviceA-Ten-GigabitEthernet3/0/1 ip address 120.1.0.1 24DeviceA-Ten-GigabitEthernet3/0/1 quit(2)      請參考以上方法配置圖中其它接口的IP地址，配置步驟這里省略  在AS 100內配置OSPF功能，保證設備間路由可達(1)      配置Device BDeviceB ospfDeviceB-ospf-1 import-rou

5、te directDeviceB-ospf-1 area 0DeviceB-ospf-1-area-0.0.0.0 quitDeviceB-ospf-1 quit(2)      配置Device CDeviceC ospfDeviceC-ospf-1 area 0DeviceC-ospf-1-area-0.0.0.0 quitDeviceC-ospf-1 quit(3)      配置Device DDeviceD ospfDeviceD-ospf-1

6、import-route directDeviceD-ospf-1 area 0DeviceD-ospf-1-area-0.0.0.0 quitDeviceD-ospf-1 quit(4)      配置Device EDeviceE ospfDeviceE-ospf-1 area 0DeviceE-ospf-1-area-0.0.0.0 quitDeviceE-ospf-1 quit  配置BGP功能(1)      配置Device A#&#

7、160;啟動BGP，指定本地AS號為200。DeviceA bgp 200# 配置Device A和Device B建立EBGP連接。DeviceA-bgp peer 120.1.0.2 as-number 100# 創建BGP IPv4單播地址族，并進入BGP IPv4單播地址族視圖。DeviceA-bgp address-family ipv4 unicast# 在BGP IPv4單播地址族視圖下，將本地路由表中到達網段的路由添加到BGP路由表中。# 使能Device A與對等體交換IPv4單播路由信息的能力。DeviceA-bgp-ipv4 pee

8、r 120.1.0.2 enableDeviceA-bgp-ipv4 quit(2)      配置Device B# 啟動BGP，指定本地AS號為100。DeviceB bgp 100# 配置Device B和Device A建立EBGP連接。DeviceB-bgp peer 120.1.0.1 as-number 200# 配置Device B和Device D建立IBGP連接。DeviceB-bgp peer 10.2.0.101 as-number 100DeviceB-bgp peer

9、 13.1.1.101 as-number 100# 創建BGP IPv4單播地址族，并進入BGP IPv4單播地址族視圖。DeviceB-bgp address-family ipv4 unicast# 使能Device B與對等體交換IPv4單播路由信息的能力。DeviceB-bgp-ipv4 peer 10.2.0.101 enable# 在BGP IPv4單播地址族視圖下，配置向對等體發布BGP路由時，將下一跳屬性修改為自身的地址。DeviceB-bgp-ipv4 peer 10.2.0.101 next-hop-local# 使能Device

10、B與對等體交換IPv4單播路由信息的能力。DeviceB-bgp-ipv4 peer 13.1.1.101 enable# 在BGP IPv4單播地址族視圖下，配置向對等體發布BGP路由時，將下一跳屬性修改為自身的地址。DeviceB-bgp-ipv4 peer 13.1.1.101 next-hop-local# 使能Device B與對等體交換IPv4單播路由信息的能力。DeviceB-bgp-ipv4 peer 120.1.0.1 enableDeviceB-bgp-ipv4 quit(3)      配置D

11、evice D# 啟動BGP，指定本地AS號為100。DeviceD bgp 100# 配置Device D和Device B建立IBGP連接。DeviceD-bgp peer 10.1.0.101 as-number 100DeviceD-bgp peer 192.168.0.101 as-number 100# 配置Device D和Device F建立EBGP連接。DeviceD-bgp peer 120.2.0.1 as-number 300# 創建BGP IPv4單播地址族，并進入BGP IPv4單播地址族視圖。DeviceD-bgp

12、 address-family ipv4 unicast# 使能Device D與對等體交換IPv4單播路由信息的能力。DeviceD-bgp-ipv4 peer 10.1.0.101 enable# 在BGP IPv4單播地址族視圖下，配置向對等體發布BGP路由時，將下一跳屬性修改為自身的地址。DeviceD-bgp-ipv4 peer 10.1.0.101 next-hop-local# 使能Device D與對等體交換IPv4單播路由信息的能力。DeviceD-bgp-ipv4 peer 192.168.0.101 enable# 在BGP IPv

13、4單播地址族視圖下，配置向對等體發布BGP路由時，將下一跳屬性修改為自身的地址。DeviceD-bgp-ipv4 peer 192.168.0.101 next-hop-local# 使能Device D與對等體交換IPv4單播路由信息的能力。DeviceD-bgp-ipv4 peer 120.2.0.1 enableDeviceD-bgp-ipv4 quit(4)      配置Device F#啟動BGP，指定本地AS號為300。DeviceF bgp 300# 配置Device F和Device D

14、建立EBGP連接。DeviceF-bgp peer 120.2.0.2 as-number 100# 創建BGP IPv4單播地址族，并進入BGP IPv4單播地址族視圖。DeviceF-bgp address-family ipv4 unicast# 在BGP IPv4單播地址族視圖下，將本地路由表中到達網段的路由添加到BGP路由表中。# 使能Device F與對等體交換IPv4單播路由信息的能力。DeviceF-bgp-ipv4 peer 120.2.0.2 enableDeviceF-bgp-ipv4 quit  配置路由策略(1)

15、60;     配置Device B# 創建ACL 2000，允許源IP地址為的報文通過。DeviceB acl number 2000DeviceB-acl-basic-2000 quit# 配置向對等體發布的路由設置本地優先級為200，并配置IBGP路由優先級為100。DeviceB route-policy local-pre permit node 10DeviceB-route-policy-local-pre if-match ip address acl 2000DeviceB-route-polic

16、y-local-pre apply local-preference 200DeviceB-route-policy-local-pre quitDeviceB bgp 100DeviceB-bgp address-family ipv4 unicastDeviceB-bgp-ipv4 peer 10.2.0.101 route-policy local-pre exportDeviceB-bgp-ipv4 preference 255 100 130DeviceB-bgp-ipv4 quit(2)      配置Device

17、0;D# 創建ACL 2000，允許源IP地址為的報文通過。DeviceD acl number 2000DeviceD-acl-basic-2000 quit# 配置向對等體發布的路由設置本地優先級為200，并配置IBGP路由優先級為100。DeviceD route-policy local-pre permit node 10DeviceD-route-policy-local-pre if-match ip address acl 2000DeviceD-route-policy-local-pre apply local-preference 200DeviceD

18、-route-policy-local-pre quitDeviceD bgp 100DeviceD-bgp address-family ipv4 unicastDeviceD-bgp-ipv4 peer 10.1.0.101 route-policy local-pre exportDeviceD-bgp-ipv4 preference 255 100 130DeviceD-bgp-ipv4 quit  配置BFD功能(1)      配置Device BDeviceB bgp 100DeviceB-

19、bgp peer 10.2.0.101 bfdDeviceB-bgp quit(2)      配置Device DDeviceD bgp 100DeviceD-bgp peer 10.1.0.101 bfdDeviceD-bgp quit  驗證配置# 從Device A上ping Device F的IP地址，可以互通。Ping 120.2.0.1 (120.2.0.1): 56 data bytes, press CTRL_C to break56 bytes from 120.2.0.1:

20、 icmp_seq=0 ttl=252 time=1.189 ms56 bytes from 120.2.0.1: icmp_seq=1 ttl=252 time=1.095 ms56 bytes from 120.2.0.1: icmp_seq=2 ttl=252 time=1.086 ms56 bytes from 120.2.0.1: icmp_seq=3 ttl=252 time=1.097 ms56 bytes from 120.2.0.1: icmp_seq=4 ttl=252 time=1.089 ms - Ping statistics for 120.2.0.1 -

21、5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss# 在Device B上通過命令display bgp peer查看BGP對等體信息，可以看到Device B與Device D建立IBGP連接，Device B與Device A建立EBGP連接，且均處于Established狀態。DeviceB display bgp peer ipv4  Local AS number: 100 Total number of peers: 3    

22、              Peers in established state: 3   Peer                    AS  MsgRcvd  MsgSent OutQ

23、 PrefRcv Up/Down  State   10.2.0.101             100        6        4    0      

24、; 1 00:00:56 Established  13.1.1.101             100        6        5    0       1 0

25、0:00:56 Established  120.1.0.1              200        6        5    0       1 00:00:

26、56 Established# 查看Device B上BFD會話信息，顯示BFD會話已被創建，且狀態為Up。DeviceB display bfd session verbose Total Session Num: 1     Up Session Num: 0     Init Mode: Active  IPv4 Session Working Under Ctrl Mode:      &

27、#160;Local Discr: 2049                 Remote Discr: 0     Session State: UP                   

28、   Interface: N/A      Min Tx Inter: 1000ms               Act Tx Inter: 1000ms      Min Rx Inter: 1000ms       

29、0;       Detect Inter: 5000ms          Rx Count: 0                        Tx Count: 910 &#

30、160;    Connect Type: Indirect           Running Up for: 00:00:00         Hold Time: 0ms               &#

31、160;     Auth mode: None       Detect Mode: Async                        Slot: 0      

32、0;   Protocol: BGP         Diag Info: No Diagnostic# 在Device B上查看的路由信息，可以看出Device B通過Device B<>Device C<>Device D這條路徑與網段通信。DeviceB display ip routing-table 120.2.0.0 24 verbose Summary Count : 3    

33、Protocol: BGP             Process ID: 0  SubProtID: 0x1                    Age: 00h24m48s      

34、 Cost: 0               Preference: 100        Tag: 0                    State: A

35、ctive Adv  OrigTblID: 0x0                OrigVrf: default-vrf    TableID: 0x2                 OrigAs: 300

36、      NibID: 0x15000001          LastAs: 300      Label: NULL              BkLabel: NULL     &#

37、160;       BkNextHop: N/ATunnel ID: Invalid          Interface: Ten-GigabitEthernet3/0/1BkTunnel ID: Invalid        BkInterface: N/A    Protocol: OSPF 

38、;           Process ID: 1  SubProtID: 0x8                    Age: 00h26m19s       Cost: 1  

39、;             Preference: 150        Tag: 1                    State: Inactive Adv  O

40、rigTblID: 0x0                OrigVrf: default-vrf    TableID: 0x2                 OrigAs: 0    

41、  NibID: 0x13000005          LastAs: 0    BkLabel: NULL             BkNextHop: N/ATunnel ID: Invalid         &

42、#160;Interface: Ten-GigabitEthernet3/0/1BkTunnel ID: Invalid        BkInterface: N/A    Protocol: OSPF            Process ID: 1  SubProtID: 0x8    

43、60;               Age: 00h26m19s       Cost: 1               Preference: 150      

44、60; Tag: 1                    State: Inactive Adv  OrigTblID: 0x0                OrigVrf: default-vrf

45、0;   TableID: 0x2                 OrigAs: 0      NibID: 0x13000003          LastAs: 0    BkLabel: NU

46、LL             BkNextHop: N/ATunnel ID: Invalid          Interface: Ten-GigabitEthernet3/0/2BkTunnel ID: Invalid        BkInterface: N/A# 在D

47、evice B<>Device C<>Device D鏈路發生故障后，從Device A上ping Device F的IP地址，可以互通。Ping 120.1.0.1 (120.2.0.1): 56 data bytes, press CTRL_C to break56 bytes from 120.2.0.1: icmp_seq=0 ttl=252 time=0.680 ms56 bytes from 120.2.0.1: icmp_seq=1 ttl=252 time=0.295 ms56 bytes from 120.2.0.1: icmp_seq=2 ttl=2

48、52 time=0.423 ms56 bytes from 120.2.0.1: icmp_seq=3 ttl=252 time=0.464 ms56 bytes from 120.2.0.1: icmp_seq=4 ttl=252 time=0.445 ms - Ping statistics for 120.2.0.1 -5 packets transmitted, 5 packets received, 0.0% packet loss# 在Device B上查看的路由信息，可以看出Device B通過Device B<>Device E<>D

49、evice D這條路徑與網段通信。<DeviceB> display ip routing-table 120.2.0.0 24 verbose Summary Count : 2    Protocol: BGP             Process ID: 0  SubProtID: 0x1       

50、60;            Age: 00h00m18s       Cost: 0               Preference: 100        Tag: 0

51、60;                   State: Active Adv  OrigTblID: 0x0                OrigVrf: default-vrf    

52、TableID: 0x2                 OrigAs: 300      NibID: 0x15000001          LastAs: 300    BkLabel: NULL