所有路由器均使用华为eNSP模拟器AR3260PC1配置IP 100.1.1.1/24连接到R1的G0/0/0接口。PC2配置IP 200.1.1.1/24连接到R5的G0/0/0接口。R1配置interface GigabitEthernet0/0/0ipaddress100.1.1.254255.255.255.0#interface GigabitEthernet0/0/1ipaddress12.1.1.1255.255.255.252#interface GigabitEthernet0/0/2ipaddress13.1.1.1255.255.255.252#interface NULL0#rip1#配置rip进程1version2#指定rip版本2network12.0.0.0#宣告网段RIP只能宣告主类网络号network13.0.0.0 network100.0.0.0R2配置interface GigabitEthernet0/0/1ipaddress12.1.1.2255.255.255.252#interface GigabitEthernet0/0/2ipaddress23.1.1.1255.255.255.252#interface NULL0#rip1version2network12.0.0.0 network23.0.0.0R3配置interface GigabitEthernet0/0/0ipaddress34.1.1.1255.255.255.252#interface GigabitEthernet0/0/1ipaddress13.1.1.2255.255.255.252#interface GigabitEthernet0/0/2ipaddress23.1.1.2255.255.255.252#interface NULL0#bgp100#启动BGP指定本地AS号为100peer34.1.1.2 as-number200#配置R3和R4建立eBGP连接#ipv4-family unicast undo synchronization import-route rip1#把RIP路由引入BGP主要是引入PC1所在路由100.1.1.0/24peer34.1.1.2enable#rip1version2network23.0.0.0 network13.0.0.0 import-route bgp#把BGP路由引入RIP主要是引入PC2所在路由200.1.1.0/24R4配置interface GigabitEthernet0/0/0ipaddress34.1.1.2255.255.255.252#interface GigabitEthernet0/0/1ipaddress45.1.1.1255.255.255.252#interface GigabitEthernet0/0/2#interface NULL0#bgp200peer34.1.1.1 as-number100peer45.1.1.2 as-number200#配置R4和R5建立iBGP连接#ipv4-family unicast undo synchronization peer34.1.1.1enablepeer45.1.1.2enablepeer45.1.1.2 next-hop-local#R4向对等体R5通告BGP路由时把下一跳设置为自己的接口地址使得R5可以学习到R4接口G0/0/0地址R5配置interface GigabitEthernet0/0/0ipaddress200.1.1.254255.255.255.0#interface GigabitEthernet0/0/1ipaddress45.1.1.2255.255.255.252#interface GigabitEthernet0/0/2#interface NULL0#bgp200peer45.1.1.1 as-number200#ipv4-family unicast#配置IPV4单播路由undo synchronization network200.1.1.0#把网络宣告进BGPpeer45.1.1.1enable可以使用命令dis bgp peer查看BGP邻居状态Established表示二者已经成功建立邻居关系其他状态Idle/Connect/Active/OpenSent/OpenConfirm代表邻居没建起来。R4dis bgp peer BGPlocalrouter ID:34.1.1.2 Local AS number:200Total number of peers:2Peersinestablished state:2Peer V AS MsgRcvd MsgSent OutQ Up/Down State Pre fRcv34.1.1.141007168001:03:16 Established445.1.1.242005354000:50:10 Established1R4注BGP邻居状态说明状态名称核心含义关键行为典型故障场景流转方向Idle空闲BGP初始状态 / 连接断开复位后的状态不主动发起TCP连接等待建连触发收到触发条件才进入Connect邻居IP路由不可达未配置peer x.x.x.x enable邻居震荡被惩罚触发建连 → Connect收到Notification/超时保持IdleConnect主动连接本地主动发起TCP连接目标端口179发起TCP三次握手等待TCP连接建立链路不稳定导致TCP握手迟迟无法完成TCP握手成功 → OpenSentTCP握手失败 → Active超时无响应 → IdleActive被动监听主动连接失败切换为被动等待对端发起TCP 179连接停止主动发起连接监听179端口等待对方接入高频故障IP互通但BGP参数不匹配AS号错误、缺少地址族enable、eBGP多跳缺失收到对端TCP连接且握手成功 → OpenSent等待超时 → IdleOpenSentOpen报文已发送TCP连接建立成功本地已发送BGP Open报文等待接收对端Open报文并校验Open报文中参数AS号、Router-ID、Holdtime、BGP版本两端BGP协商参数不一致Router-ID冲突Open报文校验通过 → OpenConfirm校验失败/收到Notification → IdleOpenConfirmOpen协商完成双方Open报文协商成功不再等待Open报文等待接收对端Keepalive报文对端Keepalive报文丢失、防火墙拦截BGP报文收到Keepalive → Established收到Notification/超时 → IdleEstablished正常建立✅ 邻居完全就绪业务可用状态正常交互Update路由、Keepalive、Notification报文交换路由条目无故障此状态代表邻居正常断开后退回Idle链路中断、Holdtime超时、收到Notification → Idle流转顺序Idle → Connect → OpenSent → OpenConfirm → EstablishedConnect失败会进入Active故障排查Idle先测连通性、检查peer是否enableActive网络能通BGP配置参数出错OpenSentOpen协商参数冲突Established邻居层面无问题故障转向路由、终端配置*所有设备配置完成后检查路由表确认路径上的设备路由通畅R3display bgp routing-table BGP Local router ID is34.1.1.1 Status codes: * - valid,- best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin:i - IGP, e - EGP, ? - incomplete Total Number of Routes:5Network NextHop MED LocPrf PrefVal Path/Ogn *12.1.1.0/300.0.0.010? *13.1.1.0/300.0.0.000? *23.1.1.0/300.0.0.000? *100.1.1.0/240.0.0.010? *200.1.1.034.1.1.20200iR4display bgp routing-table BGP Local router ID is34.1.1.2 Status codes: * - valid,- best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin:i - IGP, e - EGP, ? - incomplete Total Number of Routes:5Network NextHop MED LocPrf PrefVal Path/Ogn *12.1.1.0/3034.1.1.110100? *13.1.1.0/3034.1.1.100100? *23.1.1.0/3034.1.1.100100? *100.1.1.0/2434.1.1.110100? *i200.1.1.045.1.1.201000iR5display bgp routing-table BGP Local router ID is200.1.1.254 Status codes: * - valid,- best, d - damped, h - history, i - internal, s - suppressed, S - Stale Origin:i - IGP, e - EGP, ? - incomplete Total Number of Routes:5Network NextHop MED LocPrf PrefVal Path/Ogn *i12.1.1.0/3045.1.1.111000100? *i13.1.1.0/3045.1.1.101000100? *i23.1.1.0/3045.1.1.101000100? *i100.1.1.0/2445.1.1.111000100? *200.1.1.00.0.0.000iR5displayiprouting-table100.1.1.0 Route Flags: R - relay, D - download to fib ------------------------------------------------------------------------------ Routing Table:Public Summary Count:1Destination/Mask Proto Pre Cost Flags NextHop Interface100.1.1.0/24 IBGP2551RD45.1.1.1 GigabitEthernet0/0/1R1displayiprouting-table200.1.1.0 Route Flags: R - relay, D - download to fib ------------------------------------------------------------------------------ Routing Table:Public Summary Count:1Destination/Mask Proto Pre Cost Flags NextHop Interface200.1.1.0/24 RIP1001D13.1.1.2 GigabitEthernet0/0/2测试完成PC1和PC2可以互相ping通PC1tracert200.1.1.1#可以跟踪到PC1访问PC2网络路径为R1- R3 - R4 - R5 -PC2tracerouteto200.1.1.1,8hops max(ICMP), press CtrlC to stop1100.1.1.25415ms16ms1ms213.1.1.231ms16ms31ms334.1.1.231ms16ms15ms445.1.1.231ms32ms31ms5*200.1.1.131ms15ms PC1ping200.1.1.1 Ping200.1.1.1:32data bytes, Press Ctrl_C tobreakFrom200.1.1.1:bytes32seq1ttl124time31ms From200.1.1.1:bytes32seq2ttl124time47ms From200.1.1.1:bytes32seq3ttl124time31ms From200.1.1.1:bytes32seq4ttl124time31ms From200.1.1.1:bytes32seq5ttl124time32ms ---200.1.1.1pingstatistics ---5packet(s)transmitted5packet(s)received0.00% packet loss round-trip min/avg/max31/34/47 ms