OSPF的邻居/邻接关系拍错（troubleshooing）dis ospf error //多次使用该命令来判断问题A.相邻设备的RID不能有邻居状态的<R3>Jun 5 2018 19:32:52-08:00 R3 %%01OSPF/4/CONFLICT_ROUTERID_INTF(l)[2]:OSPF Router id conflict is detected on interface. (ProcessId=256, RouterId=4.4.0.0, AreaId=34.0.0.0, InterfaceName=Serial2/0/0, IpAddr=3.34.1.10, PacketSrcIp=4.34.1.10) //在s2/0/0接口上检测到了RID冲突<R3>dis ospf error OSPF Process 1 with Router ID 0.0.4.4 OSPF error statistics General packet errors: 0 : IP: received my own packet 0 : Bad packet 0 : Bad version 0 : Bad checksum 0 : Bad area id 0 : Drop on unnumbered interface 0 : Bad virtual link 0 : Bad authentication type 0 : Bad authentication key 0 : Packet too small 0 : Packet size > ip length 0 : Transmit error 0 : Interface down 0 : Unknown neighbor 0 : Bad net segment 0 : Extern option mismatch 33 : Router id confusion //表明RID冲突补充一点：同一区域的不相邻设备RID冲突，缺少路由B、链路上区域ID不匹配[R3]dis ospf error OSPF Process 1 with Router ID 33.1.1.1 OSPF error statistics General packet errors: 0 : IP: received my own packet 0 : Bad packet 0 : Bad version 0 : Bad checksum 4 : Bad area id //区域ID不匹配 0 : Drop on unnumbered interface 0 : Bad virtual link 0 : Bad authentication type 0 : Bad authentication key 0 : Packet too small 0 : Packet size > ip length 0 : Transmit error 1 : Interface down 0 : Unknown neighbor 0 : Bad net segment 0 : Extern option mismatch 0 : Router id confusion C、Hello和死亡时间都需要匹配什么场景下会修改时间呢？在没有其他检测机制的前提下（BFD），协议本身为了加速检测邻居时间和收敛时间[R3]dis ospf error OSPF Process 1 with Router ID 33.1.1.1 OSPF error statistics General packet errors: 0 : IP: received my own packet 303 : Bad packet 0 : Bad version 0 : Bad checksum 38 : Bad area id 0 : Drop on unnumbered interface 0 : Bad virtual link 0 : Bad authentication type 0 : Bad authentication key 0 : Packet too small 0 : Packet size > ip length 0 : Transmit error 1 : Interface down 0 : Unknown neighbor 0 : Bad net segment 0 : Extern option mismatch 0 : Router id confusionHELLO packet errors: 0 : Netmask mismatch 303 : Hello timer mismatch //先检测Hello，死亡时间暂时不关心 0 : Dead timer mismatch 0 : Virtual neighbor unknown 0 : NBMA neighbor unknown 0 : Invalid Source Address[R3]dis ospf error OSPF Process 1 with Router ID 33.1.1.1 OSPF error statistics General packet errors: 0 : IP: received my own packet 453 : Bad packet 0 : Bad version 0 : Bad checksum 38 : Bad area id 0 : Drop on unnumbered interface 0 : Bad virtual link 0 : Bad authentication type 0 : Bad authentication key 0 : Packet too small 0 : Packet size > ip length 0 : Transmit error 1 : Interface down 0 : Unknown neighbor 0 : Bad net segment 0 : Extern option mismatch 0 : Router id confusionHELLO packet errors: 0 : Netmask mismatch 350 : Hello timer mismatch 103 : Dead timer mismatch //死亡时间不匹配 0 : Virtual neighbor unknown 0 : NBMA neighbor unknown 0 : Invalid Source Address[R3-Serial2/0/0]ospf timer dead 1Error: The dead interval must be greater than the hello interval. //华为设备不能把死亡时间配置的小于等于hello时间！D、多点接入网络的掩码一致（2类LSA）dis ospf errorHELLO packet errors: 26 : Netmask mismatch //网络掩码不匹配 0 : Hello timer mismatch 0 : Dead timer mismatch 0 : Virtual neighbor unknown 0 : NBMA neighbor unknown 0 : Invalid Source Address 多点接入网段不一致：[SW1-Vlanif30]dis ospf error OSPF Process 1 with Router ID 10.10.10.10 OSPF error statistics General packet errors: 0 : IP: received my own packet 56 : Bad packet 0 : Bad version 0 : Bad checksum 0 : Bad area id 0 : Drop on unnumbered interface 0 : Bad virtual link 0 : Bad authentication type 0 : Bad authentication key 0 : Packet too small 0 : Packet size > ip length 0 : Transmit error 6 : Interface down 0 : Unknown neighbor 24 : Bad net segment //错误的网段 //点到点网络不受掩码的影响（Hello中掩码位会显示0.0.0.0即不检测）：请问点到点网络建立OSPF邻居受子网影响么？在点到点的OSPF网络，掩码、子网并不要求，可以完成邻居关系请问如果一个接口没有配置IP地址可以建立邻居么？[R4-Serial2/0/0]ip address unnumbered interface LoopBack 0 //串口借用环回接口的地址作为源发送报文，通常会用到广域网IP地址匮乏的环境中E、MTU一致性检测默认情况下华为设备上不检测MTU一致性，除非俩端都配置 ospf mtu-enable[SW1-Vlanif30]dis th#interface Vlanif30 ip address 10.1.30.10 255.255.255.0 ospf mtu-enable ospf enable 1 area 0.0.0.34[R3]dis cu int g0/0/1[V200R003C00]#interface GigabitEthernet0/0/1 mtu 1504 ip address 10.1.30.4 255.255.255.0 ospf mtu-enable ospf enable 1 area 0.0.0.34[R3]dis ospf peer brief OSPF Process 1 with Router ID 33.1.1.1 Peer Statistic Information ---------------------------------------------------------------------------- Area Id Interface Neighbor id State 0.0.0.34 GigabitEthernet0/0/1 10.10.10.10 ExStart 0.0.0.34 Serial2/0/0 0.0.4.4 Full 会卡到exstart/exchange状态，注意并不是2-waydis ospf errorDD packet errors: 0 : Neighbor state low 0 : Unknown LSA type 2 : MTU option mismatch //MTU不匹配 F、标志位的一致性Option中 E=1代表可以接受外部路由，E=0NP，和NSSA特殊区域有关