debug OSPF

R1#debug ip ospf adj

*Sep 23 19:35:38.739: OSPF: Interface FastEthernet0/0 going Down

*Sep 23 19:35:38.739: OSPF: 1.1.1 .1 address 192.168.10.1 . FastEthernet0/0 is dead, state DOWN

*Sep 23 19:35:38.739: OSPF: Neighbor change Event . interface FastEthernet0/0

*Sep 23 19:35:38.739: OSPF: DR/BDR election . FastEthernet0/0

*Sep 23 19:35:38.739: OSPF: Elect BDR 0.0.0 .0

*Sep 23 19:35:38.739: OSPF: Elect DR 192.168.235.1

*Sep 23 19:35:38.739: OSPF: Elect BDR 0.0.0 .0

*Sep 23 19:35:38.743: OSPF: Elect DR 192.168.235.1

*Sep 23 19:35:38.743:        DR: 192.168.235.1 (Id)   BDR: none

*Sep 23 19:35:38.743: OSPF: 192.168.235.1 address 192.168.10.2 . FastEthernet0/0 is dead, state DOWN

[EC1] 

*Sep 23 19:47:40.403: OSPF: Cannot see ourself in hello from 192.168.235.1 . FastEthernet0/0, state INIT [EC2] 

 

*Sep 23 19:35:38.743: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.235.1 . FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached

*Sep 23 19:35:38.747: OSPF: Neighbor change Event . interface FastEthernet0/0

*Sep 23 19:35:38.747: OSPF: DR/BDR election . FastEthernet0/0

*Sep 23 19:35:38.747: OSPF: Elect BDR 0.0.0 .0

*Sep 23 19:35:38.747: OSPF: Elect DR 0.0.0 .0

*Sep 23 19:35:38.747:        DR: none    BDR: none

*Sep 23 19:35:38.747: OSPF: Remember old DR 192.168.235.1 (id)

[EC3] 

*Sep 23 19:35:38.819: OSPF: Interface FastEthernet0/0 going Up

*Sep 23 19:35:38.819: OSPF: i_up : interface is down

*Sep 23 19:35:39.243: OSPF: Build router LSA for area 0, router ID 1.1.1 .1, seq 0x80000001

*Sep 23 19:35:47.459: OSPF: 2 Way Communication to 192.168.235.1 . FastEthernet0/0, state 2WAY

*Sep 23 19:35:47.459: OSPF: Backup seen Event before WAIT timer . FastEthernet0/0

*Sep 23 19:35:47.459: OSPF: DR/BDR election . FastEthernet0/0

*Sep 23 19:35:47.459: OSPF: Elect BDR 1.1.1 .1

*Sep 23 19:35:47.463: OSPF: Elect DR 192.168.235.1

*Sep 23 19:35:47.463: OSPF: Elect BDR 1.1.1 .1

*Sep 23 19:35:47.463: OSPF: Elect DR 192.168.235.1

*Sep 23 19:35:47.463:        DR: 192.168.235.1 (Id)   BDR: 1.1.1 .1 (Id)

[EC4] 

*Sep 23 19:35:47.463: OSPF: Send DBD to 192.168.235.1 . FastEthernet0/0 seq 0x727 opt 0x52 flag 0x7 len 32

*Sep 23 19:35:47.535: OSPF: Rcv DBD from 192.168.235.1 . FastEthernet0/0 seq 0x1921 opt 0x52 flag 0x7 len 32  mtu 1500 state EXSTART

*Sep 23 19:35:47.535: OSPF: NBR Negotiation Done. We are the SLAVE

[EC5] 

*Sep 23 19:35:47.535: OSPF: Send DBD to 192.168.235.1 . FastEthernet0/0 seq 0x1921 opt 0x52 flag 0x2 len 52

*Sep 23 19:35:47.583: OSPF: Rcv DBD from 192.168.235.1 . FastEthernet0/0 seq 0x1922 opt 0x52 flag 0x3 len 52  mtu 1500 state EXCHANGE

*Sep 23 19:35:47.583: OSPF: Send DBD to 192.168.235.1 . FastEthernet0/0 seq 0x1922 opt 0x52 flag 0x0 len 32

[EC6] 

*Sep 23 19:35:47.587: OSPF: Database request to 192.168.235.1

*Sep 23 19:35:47.587: OSPF: sent LS REQ packet to 192.168.10.2, length 12

[EC7] 

*Sep 23 19:35:47.607: OSPF: Rcv DBD from 192.168.235.1 . FastEthernet0/0 seq 0x1923 opt 0x52 flag 0x1 len 32  mtu 1500 state EXCHANGE

*Sep 23 19:35:47.607: OSPF: Exchange Done with 192.168.235.1 . FastEthernet0/0

[EC8] 

 

*Sep 23 19:35:47.607: OSPF: Send DBD to 192.168.235.1 . FastEthernet0/0 seq 0x1923 opt 0x52 flag 0x0 len 32

*Sep 23 19:35:47.611: OSPF: Synchronized with 192.168.235.1 . FastEthernet0/0, state FULL

*Sep 23 19:35:47.611: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.235.1 . FastEthernet0/0 from LOADING to FULL, Loading Done

[EC9]  向DR返回LS Acknowlege報文，LSDB達到同步。Full狀態

 

*Sep 23 19:35:47.967: OSPF: Build router LSA for area 0, router ID 1.1.1 .1, seq 0x80000002

*Sep 23 19:35:53.347: OSPF: Build router LSA for area 0, router ID 1.1.1 .1, seq 0x80000005

*Sep 23 19:35:57.419: OSPF: Neighbor change Event . interface FastEthernet0/0

*Sep 23 19:35:57.419: OSPF: DR/BDR election . FastEthernet0/0

*Sep 23 19:35:57.419: OSPF: Elect BDR 1.1.1 .1

*Sep 23 19:35:57.419: OSPF: Elect DR 192.168.235.1

*Sep 23 19:35:57.419:        DR: 192.168.235.1 (Id)   BDR: 1.1.1 .1 (Id)

若是是在DR上重啓OSPF進程的話，也大體相同，只是原來DR的位置會被BDR頂替上。

---

 [EC1] 其實從進程開始重啓後，立刻已經開始了一輪DR競選。狀態爲Down

 [EC2] 在hello包裏未發現本身的router-id，因此狀態變爲  INIT

 

 [EC3] 重啓ospf進程後，當路由器啓動進程後，首先發送hello報文，構建一個空包BDR和DR的競選（BDR和DR的地址都是全0），並構建一個wait timer，在這時間內若是沒有收到域內DR/BDR的通告，就會發出通告說本身要參加競選啦。這裏的結果是收到了DR的通告（router-id：192.168.235.1是老的DR），而並沒BDR。

 

 [EC4] 下一步，當與鄰居發生鄰接關係後（state :2WAY），發起本身的競選通告!前面指出，DR有了，BDR還沒人當呢，因此hello報文裏BDR部分就把本身的R-ID填上了。最後競選成功，當了BDR。

 

 [EC5] 接下來進入EXSTART狀態。經過互相發送DBD報文，協商參數，決定了本身是從路由器身份。

 

 [EC6] 交換雙方的LSA頭

 

 [EC7] 發送 LSQ 向 DR 請求本身沒有的 LSA

 [EC8] 從主路由器收到所有 LSU ， Exchange 狀態完成

 [EC9] 向主路由器返回 LSACK ， LSDB 同步完成，達到 Full 狀態