1、來源： HYPERLINK /tech/cisco/jiaocai/ccnp/20080428/294572.html /tech/cisco/jiaocai/ccnp/20080428/294572.html一實驗目的1）理解Multicast的一些基本概念。2）掌握pim dense-mode的基本配置。3）理解 pim dense-mode 的 flood 和 prune 過程。4）理解 pim dense-mode 的 assert 機制5）掌握cgmp的配置，及其優(yōu)點。6）掌握pim sparse-mode的基本配置。二、實驗拓撲和器材so.1 fB/l192.16H.2jc fB

2、. B CJ600)chinaitlab中國IT實驗室拓撲如上所示，需要路由器四臺、交換機一臺，主機三臺（一臺能作組播的服務 器，需要Server級的windows操作系統(tǒng)）。三、實驗原理1.組播基本原理Multicast應用在一點對多點、多點對多點的網(wǎng)絡傳輸中，可以大大的減少網(wǎng)絡的負載。 因此，Multicast廣泛地應用在流媒體的傳輸、遠程教學、視頻/音頻會議等網(wǎng)絡應用方面。Multicast 采用 D 類 IP 地址，即 55。其中 -55是保留地址，55 是私有地址，類似于 unicast的私有地址。Multicast的IP地址與MAC地址的映射:MAC地址有48位，前面24位規(guī)定為0

3、1-00-5E， 接著一位為0，后面23位是IP地址的后23位。路由器間要通過組播協(xié)議（如DVMRP、MOSPF、PIM）來建立組播樹和轉發(fā)組播數(shù) 據(jù)包。組播樹有兩類：源樹和共享樹。多播時，路由器采用組管理協(xié)議IGMP來管理和維護主機參與組播。IGMP協(xié)議v1中，主機發(fā)送report包來加入組；路由器發(fā)送query包來查詢主機（地址是）， 同一個組的同一個子網(wǎng)的主機只有一臺主機成員響應，其它主機成員抑制響應。一般路由器 要發(fā)送3次query包，如果3次都沒響應，才認為組超時（約3分鐘）。IGMPv2中，主 機可以發(fā)送leave信息給路由器（地址）；路由器收到信息后，發(fā)送一個特別的 query包

4、，在3秒內(nèi)沒收到組成員響應，就認為組超時。由于組播的MAC不是具體某臺主機的MAC，根據(jù)交換機的工作原理，交換機會 對組播數(shù)據(jù)包進行廣播。因此，對某些不參加組播的主機而言，這些都是不必要的流。為了 解決這個問題，cisco公司開發(fā)了 CGMP協(xié)議。該協(xié)議用于管理參與組播的主機。每當有 主機加入或離開某個組時，路由器就會把該主機的多播IP地址（轉換成組播MAC地址）、 主機的C地址以及消息類型（加入或離開）以CGMP消息告知交換機。交換機根據(jù)這些 信息就可以建立起組播轉發(fā)表。2. PIM協(xié)議Cisco的路由器只支持PIM組播協(xié)議。PIM是一種可利用多種單播路由表（如 EIGRP、OSPF、BGP

5、和靜態(tài)路由等）的組播路由協(xié)議，它根據(jù)這些路由表實現(xiàn)組播數(shù)據(jù) 的轉發(fā)。盡管它是組播路由協(xié)議，然而它實際上只是使用單播路由表來完成RPF檢驗功能， 并沒有重新建立組播路由表。不像其他的路由協(xié)議，PIM并不會在路由之間收發(fā)路由更新 信息。PIM分為Dense-mode與Sparse-mode兩種。密集模式的PIM（PIM-DM）使用“推” 的方式，把組播流向網(wǎng)絡的各個地方轉發(fā)，從而把流推”給不同接收者。這種方式適用于網(wǎng) 絡中的各個子網(wǎng)都有接收者（即接收者密集）的情況。PIM-DM 一開始向網(wǎng)絡中的各處發(fā)組 播流，路由器每隔3分鐘檢查一次自己是否還存在“下游”的鄰居，如果沒有（即它無需轉發(fā) 組播流），

6、就把這個流“剪”掉（即不再轉發(fā)）。路由器會積累數(shù)據(jù)流所帶有的源和組的信息， 使得“下游”的路由器可以建立它們的組播轉發(fā)表PIM-DM只支持源樹，而無法使用共享樹。松散模式的PIM （PIM-SM）使用“拉”的方式，只有存在接收者的網(wǎng)段才會接收到 數(shù)據(jù)流（即接收者把流“拉”出來）。PIM-SM通過在共享樹中轉發(fā)數(shù)據(jù)包來散布組播源的信 息。PIM-SM使用共享樹（至少在組播開始的時候需要使用），因此，它需要指定一個匯聚 點（RP）。源在RP中“注冊”后，數(shù)據(jù)就通過共享樹轉發(fā)到接收者。一旦其它路由器收到從 共享樹來的數(shù)據(jù)后，就知道了數(shù)據(jù)的源在哪里。于是，路由器就會向源發(fā)送PIM （S，G） 加入信息

7、。在反向路徑上的每個路由器比較自己的單播路由表中它到RP的度量和它到源的度量，如果到源的度量更優(yōu)，它就會繼續(xù)發(fā)送PIM （S, 6）加入信息。否則（包括度量相 等的情況），PIM（S，G）信息就會沿著RP的方向來發(fā)送。這樣，就生成了共享樹和源樹。如下圖所示的單向共享樹，靠近源的路由器先向RP注冊，然后在源和RP之間生成源樹， 數(shù)據(jù)通過共享樹（*，G）到達接收者。ZjI UhTDCjrrn iKlrM- rrw?RK.-sno-*=! I*dh my mlinaitlab泛出國IT實驗室由于共享樹并不是源到接收者的最優(yōu)路徑，因此，當流量超過某個門限值后，路 由器會動態(tài)地生成源樹。該門限值默認的情

8、況為0 （例如，在Cisco的路由器中，可通過ip pim spt-thresholdinfinity命令來修改該門限值）。同時，為了減輕RP的負擔，在PIM-SM 的第二個版本中，規(guī)定源要周期性的向RP注冊，使得RP不必要維護大量的源的信息。五、實驗步驟：路由器基本配置1）按上面的拓撲配置好各臺路由器及主機的IP地址；2）啟用 eigrp 協(xié)議，AS 號為 100，配置 no auto-summary。每臺路由器上啟動multicast-routing。在全局配置模式下鍵入：（config）#ip multicast-routing路由器的每一個端口上配置pim dense-mode命令如下

9、：（config-if）#ip pim dense-mode驗證multicast的相關命令show ip pim neighbor :觀察 pim 鄰居；show ip pim interface :觀察端口上的 pim 信息；show ip mroute :觀察 multicast 路由表； debug ip pim :顯示 pim 的 debug 信息； debug ip igmp :顯示 igmp 信息。5. Multicast 驗證驗證分為四個階段進行驗證，都采用第4點所列出的命令1）在服務器未連接時（拔掉與server連接的線）只看到關于0的多播組的信息，看不到其它多播組的信息。2

10、）接上與服務器連接的網(wǎng)線，但client還未連接可以看到服務器上啟動的節(jié)目組的多 播組信息。但由于沒有client，穩(wěn)定狀況下所有端口都是prune狀態(tài)的。3）在client端打開media player，連接上服務器訪問組播用以下命令： http:/192.168.52/station1.nsc。打開服務器上的*.nsc文件，等讀取了*.nsc文件信息后，就 自動開始播放節(jié)目，因.nsc文件中已經(jīng)包含訪問組播服務器所需要的組播IP地址、端口號、 流媒體文件等信息。這時就可以看到一些端口的狀態(tài)由prune變成forward，打開debug ip igmp就可以看到主機加入某個組的信息。4）斷開

11、client與服務器的連接，即關閉media player的播放可以看到主機離開某個 組的信息，并且在show ip mroute后發(fā)現(xiàn)某些端口已經(jīng)有forward變?yōu)閜rune。6.配置cgmp1）配置前，在 switch 上用 show mac-address-table 以及 show cgmp 查看一 下相關信息，以同配置后的信息進行對比。2）在A及Switch上配置cgmp。對于路由器A，配置命令是在端口（連接主機的 以太網(wǎng)口）模式下，鍵入：（config-if）#ip cgmp對于Switch，配置命令是：（config）#cgmp leave-processing3） 驗證在 A

12、上，用 debug ip cgmp查看debug信息；在 Switch 上用命令debug cgmp 查看debug信息。但要注意1900沒有debug命令。在 Switch上再用命令show mac-address-table以及show cgmp看看前后有什么 不同。7.配置pim sparse-mode（配置之前要把PIM Dense-mode的設置去掉）1）基本配置每臺路由器上啟動multicast-routingo在全局配置模式下鍵入：（config）#ip multicast-routing路由器的每一個端口上配置pim dense-mode命令如下：(config-if)#ip

13、pim sparse-dense-mode /配己置了 RP 后自動為 sparse-mode 式，否則為 dense-mode。static-RP 的 PIM-SM靜態(tài)RP的配置時，只需要在連接有client的路由器上配置，用于指定需要去注 冊的RP的IP地址。還可以通過相應的ACL來控制哪些組的RP是誰。一臺路由上可 以指定多個RP。靜態(tài)指定RP時，RP那臺路由器并不需要知道它自己就是RP。這就是說RP無需 本身無需配置。A、C和D的配置一樣：Router (config)#access-list 20 deny 9Router (config)#access-list 20 deny 0

14、Router (config)#access-list 20 permit 55Router(config)#ip pim rp-address 0 20 /0 為 RouterB 的回環(huán) 接口地址B的配置：Router (config)#int loopback 0Router (config-if)#ip address 0 Router (config-if)#no shutRouter (config)#router eigrp 100Router (config-router)#network 55驗證：1) show ip pim rp 或 show ip pim rp mappi

15、ngs2)與密集模式的相同。auto-RP 的 PIM-SM由于靜態(tài)指定RP必須為每一臺末端(連接有client)的路由器手工配置RP，且 當RP改變時還要手動進行更改，帶來很大的管理工作量。而自動RP則可以解決這個問 題。自動RP模型中，分為候選RP和RP映射代理。前者可以配置作為某些組的候選RP 而以9多播組地址向后者通告；后者接收這些信息后再以0得多播組地 址通告候選RP的信息。末端路由器接收到這個0多播組的信息后就可以知道有 哪些RP，并且這些RP對應哪些多播組，從而可以自動發(fā)現(xiàn)RP。候選RP和RP映射代理可以相互獨立，不一定屬于同一臺路由器。但為了可靠 起見，而通常將它們合為一體。本

16、實驗中B是兩者合為一體的，但C則只是候選RP通 告而不做RP映射代理。A和D的配置一樣：Router(config)#access-list 20 deny 9Router(config)#access-list 20 deny 0Router(config)#access-list 20 permit 55Router(config)#ip pim rp-address 20/ 為不存在的地址，目的是讓些非自動RP通告的多播組找不到RP。在協(xié)議中這稱為sink RP。B的配置：Router (config)#access-list 20 deny 9Router (config)#acces

17、s-list 20 deny 0Router (config)#access-list 20 permit 55Router (config)#ip pim rp-address 20注釋同上Router (config)#access-list 30 permit 0作為 0 組的候選RPRouter(config)#ip pim send-rp-announce loopback 0 scope 32 group-list 30/作為符合ACL30條件的多播組的候選RP而向RP mapping Agent通告Router(config)#ip pim send-rp-discovery l

18、oopback 0 scope 32/作為RP的mapping Agent而向0組通告RP的信息C的配置：Router (config)#int loopback 0Router (config-if)#ip address Router (config-if)#no shutRouter (config)#router eigrp 100Router (config-router)#network 55Router (config)#access-list 20 deny 9Router (config)#access-list 20 deny 0Router (config)#access

19、-list 20 permit 55Router (config)#ip pim rp-address 20注釋同上二理 S UO 0=01 PUCDS Wd tLnocooo nl009 36l EOML_ 理 S UO 0=01 PMooCDlrWdoLnocooo P(DOU6 一O(Nuoldo UMOUMUn SBLIoMOBd O-OH -l/M-d 二Lnocoo。 0.0009 L.CN6 L eo4=0巫(ds UO 0=01 PMooCDlrWd 二go”。(Ds UO 0=01 PUCDS Wd 二蟲。cooo 0ou(DLIilJlsBLJ_uo 0=01 PUCDS

20、Wdb寸ocooo l_b_(ds UO 0=01 PUCDS Wd 忠ocooo nl009 36l EOML_ 理 S uo 0=01 PMoslrWd 總ocooo P(DOU6 一O(Nuoldo UMOUMUn SBLIoMOBd O-OH -l/M-d 二eocoo。 0.0009 L.CN6 L eo4=0巫(ds uo 0=01 PMooCDlrWd 二eocoo。(Ds UO 0=01 PUCDS Wd 二eocoo。0ou(DLIilJlsBLJ_uo 0=01 PUCDS WdOLOCOOO 。寸 Lose0M(de_1 dnob山 drnox 山 6u_lBpdn 1君

21、0一ooocoo。S8nos ooL.i7oo9 36L EOMeCDpoluo寸 L.o.寸窩 dno&0Mp0$dno0PMooCDlrtrIAIQooocooo。寸 Lose 0ML.i7009L.(N6L EOM01(du(d 山 isblluo lod(Dlr(N p(D(Do(Dlr-dIAIo-ooocoo。 ooEoLImlsBLJ-uo。寸 L.o.寸N(N0Mlod PUCDStrIAIoooocooo-Lu 一 ddlu6 一 d 一 6nq(Dp。弟 motr(一)弟* ocii咪史淵林，叩Drlr艷回“電箱00 ls_ldno6 ecoCDdoos 0 MOBqdoo

22、-CDounouu 甲 dYpuCDs E 一 d d_#84uoo)(DlnolrN(N.69L.(N.i7(N(N1一 E(Dd 00 is一lss(D00B#(6 一Muo。)(Dlnolr00:31:00: IGMP: Send v2 general Query on FastEthernet000:31:00: IGMP: Set report delay time to 2.2 seconds for 0 on FastEthernet000:31:03: IGMP: Send v2 Report for 0 on FastEthernet000:31:03: IGMP: Rece

23、ived v2 Report on FastEthernet0 from for 000:31:03: IGMP: Received Group record for group 0, mode 2 fromfor 0sources00:31:03: IGMP: Updating EXCLUDE group timer for 000:31:16: PIM: Send v2 Hello on FastEthernet000:31:21: PIM: Send v2 Hello on Serial000:31:21: PIM: Received v2 Hello on Serial0 from 0

24、0:31:21: PIM: Hello packet has unknown option 20, ignored00:31:23: PIM: Received v2 Hello on Serial1 from 00:31:24: PIM: Send v2 Hello on Serial100:31:46: PIM: Send v2 Hello on FastEthernet000:31:51: PIM: Send v2 Hello on Serial000:31:51: PIM: Received v2 Hello on Serial0 from 00:31:51: PIM: Hello p

25、acket has unknown option 20, ignored00:31:53: PIM: Received v2 Hello on Serial1 from 00:31:54: PIM: Send v2 Hello on Serial100:32:00: IGMP: Send v2 general Query on FastEthernet000:32:00: IGMP: Set report delay time to 3.8 seconds for 0 on FastEthernet000:32:04: IGMP: Send v2 Report for 0 on FastEth

26、ernet000:32:04: IGMP: Received v2 Report on FastEthernet0 from for 000:32:04: IGMP: Received Group record for group 0, mode 2 fromfor 0sourcesRouter_C#sh ip mrouIP Multicast Routing TableFlags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,L - Local, P - Pruned, R - RP-bit set

27、, F - Register flag,T - SPT-bit set, J - Join SPT, M - MSDP created entry,X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,U - URD, I - Received Source Specific Host ReportOutgoing interface flags: H - Hardware switchedTimers: Uptime/ExpiresInterface state: Interface, Next-Hop or V

28、CD, State/Mode(*, 0), 00:26:52/00:00:00, RP , flags: DCLIncoming interface: Null, RPF nbr Outgoing interface list:Serial1, Forward/Dense, 00:26:43/00:00:00Serial0, Forward/Dense, 00:26:47/00:00:00FastEthernet0, Forward/Dense, 00:26:52/00:00:00Router_C#sh ip pim neighborPIM Neighbor TableNeighborAddr

29、essInterfaceUptime/Expires Ver DRPrio/ModeSerial000:28:48/00:01:29 v21 /SSerial100:28:44/00:01:30 v21 /B SRouter_C#sh ip pim interfaceAddressInterfaceVer/ Nbr Query DRDRFastEthernet0Mode Count Intvl Priorv2/D 0301Serial0v2/D1301Serial1v2/D1301(2) Router_Ashow ip mroute01:12:33: PIM: Send v2 Hello on

30、 Serial0/101:12:33: PIM: Received v2 Hello on Serial0/1 from routeIP Multicast Routing TableFlags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,L - Local, P - Pruned, R - RP-bit set, F - Register flag,T - SPT-bit set, J - Join SPT, M - MSDP created entry,X - Proxy Join Timer

31、Running, A - Candidate for MSDP Advertisement,U - URD, I - Received Source Specific Host Report, s - SSMOutgoing interface flags: H - Hardware switchedTimers: Uptime/ExpiresInterface state: Interface, Next-Hop or VCD, State/Mode(*, 0), 00:11:33/00:00:00, RP , flags: DCLIncoming interface: Null, RPF

32、nbr Outgoing interface list:Serial0/1, Forward/Dense, 00:11:33/00:00:00FastEthernet0/0, Forward/Dense, 00:11:33/00:00:00(3)Router_BRouterB#show ip pim neighborPIM Neighbor TableNeighborInterfaceUptime/Expires Ver DRAddressPrio/ModeEthernet001:08:38/00:01:39 v21 / SSerial000:45:55/00:01:15 v21 / SRou

33、terB# show ip mrouteIP Multicast Routing TableFlags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,L - Local, P - Pruned, R - RP-bit set, F - Register flag,T - SPT-bit set, J - Join SPT, M - MSDP created entry,X - Proxy Join Timer Running, A - Candidate MSDP Advertisement,U -

34、URD, I - Received Source Specific Host Report, Z - Multicast TunnelY - Joined MDT-data group, y - Sending to MDT-data groupOutgoing interface flags: H - Hardware switchedTimers: Uptime/ExpiresInterface state: Interface, Next-Hop or VCD, State/Mode(*, 0), 01:09:10/00:02:53, RP , flags: DCLIncoming in

35、terface: Null, RPF nbr Outgoing interface list:Serial0, Forward/Dense, 00:46:25/00:00:00Ethernet0, Forward/Dense, 01:09:10/00:00:00RouterB#debug ip pimPIM debugging is onRouterB#debug ip igmpIGMP debugging is onRouterB#*Mar 1 01:10:15.123: PIM(0): Received v2 Hello on Ethernet0 from *Mar 1 01:10:19.

36、039: PIM(0): Send periodic v2 Hello on Ethernet0*Mar 1 01:10:20.694: PIM(0): Received v2 Hello on Serial0 from *Mar 1 01:10:28.959: PIM(0): Send periodic v2 Hello on Serial0*Mar 1 01:10:41.125: IGMP(0): Received v2 Query on Ethernet0 from *Mar 1 01:10:41.129: IGMP(0): Set report delay time to 3.6 se

37、conds for 0on Ethernet0*Mar 1 01:10:44.780: IGMP(0): Send v2 Report for 0 on Ethernet0*Mar 1 01:10:44.784: IGMP(0): Received v2 Report on Ethernet0 fromfor0*Mar 1 01:10:44.787: IGMP(0): Received Group record for group 0, mode 2 fromfor 0 sources*Mar 1 01:10:44.791: IGMP(0): MRT Add/Update Ethernet0

38、for (*,0) by 0*Mar 1 01:10:44.795: IGMP(0): Updating EXCLUDE group timer for 0*Mar 1 01:10:45.141: PIM(0): Received v2 Hello on Ethernet0 from *Mar 1 01:10:48.799: PIM(0): Send periodic v2 Hello on Ethernet0*Mar 1 01:10:50.724: PIM(0): Received v2 Hello on Serial0 from *Mar 1 01:10:58.719: PIM(0): S

39、end periodic v2 Hello on Serial0*Mar 1 01:11:15.166: PIM(0): Received v2 Hello on Ethernet0 from *Mar 1 01:11:18.670: PIM(0): Send periodic v2 Hello on Ethernet0*Mar 1 01:11:20.777: PIM(0): Received v2 Hello on Serial0 from *Mar 1 01:11:28.662: PIM(0): Send periodic v2 Hello on Serial0*Mar 1 01:11:4

40、1.149: IGMP(0): Received v2 Query on Ethernet0 from *Mar 1 01:11:41.153: IGMP(0): Set report delay time to 6.6 seconds for 0 on Ethernet0*Mar 1 01:11:45.165: IGMP(0): Received v2 Report on Ethernet0 fromfor0*Mar 1 01:11:45.169: IGMP(0): Received Group record for group 0, mode 2 fromfor 0 sources*Mar

41、1 01:11:45.172: IGMP(0): Cancel report for 0 on Ethernet0*Mar1 01:11:45.176: IGMP(0): MRT Add/Update Ethernet0 for (*,0) by 0*Mar 1 01:11:45.180: IGMP(0): Updating EXCLUDE group timer for 0*Mar 1 01:11:45.184: PIM(0): Received v2 Hello on Ethernet0 from *Mar 1 01:11:48.573: PIM(0): Send periodic v2

42、Hello on Ethernet0*Mar 1 01:11:50.795: PIM(0): Received v2 Hello on Serial0 from *Mar 1 01:11:58.505: PIM(0): Send periodic v2 Hello on Serial0*Mar 1 01:12:15.171: PIM(0): Received v2 Hello on Ethernet0 from *Mar 1 01:12:18.353: PIM(0): Send periodic v2 Hello on Ethernet0*Mar 1 01:12:20.865: PIM(0):

43、 Received v2 Hello on Serial0 from /server on , no multicast stream(1)Router_Cdebug ip igmp/pim00:58:00: IGMP: Send v2 general Query on FastEthernet000:58:00: IGMP: Set report delay time to 9.2 seconds for 0 on FastEthersh ip mrouteRouter_C#clear ip mrou *Router_C#00:58:10: IGMP: Send v2 Report for

44、0 on FastEthernet000:58:10: IGMP: Received v2 Report on FastEthernet0 from for 000:58:10: IGMP: Received Group record for group 0, mode 2 fromfor 0sources00:58:10: IGMP: Updating EXCLUDE group timer for 000:58:11: IGMP: Send v2 Report for 0 on FastEthernet000:58:11: IGMP: Received v2 Report on FastE

45、thernet0 from for 000:58:11: IGMP: Received Group record for group 0, mode 2 fromfor 0sources00:58:11: IGMP: Updating EXCLUDE group timer for 000:58:12: PIM: Building Graft message for 0, Seriall: no entries00:58:12: PIM: Building Graft message for 0, Serial0: no entries00:58:12: PIM: Building Graft

46、 message for 0, FastEthernet0: no entries00:58:16: PIM: Send v2 Hello on FastEthernet000:58:21: PIM: Send v2 Hello on Serial000:58:24: PIM: Received v2 Hello on Serial0 from 00:58:24: PIM: Hello packet has unknown option 20, ignored00:58:24: PIM: Received v2 Hello on Serial1 from 00:58:24: PIM: Send

47、 v2 Hello on Serial100:58:46: PIM: Send v2 Hello on FastEthernet000:58:48: PIM: Send v2 Prune on Serial0 to for (/32, 34)一沒有 CILENT00:58:48: PIM: Send v2 Prune on Serial0 to for (/32, 92)00:58:51: PIM: Send v2 Hello on Serial000:58:54: PIM: Received v2 Hello on Serial1 from 00:58:54: PIM: Received v

48、2 Hello on Serial0 from 00:58:54: PIM: Hello packet has unknown option 20, ignored00:58:54: PIM: Send v2 Hello on Serial100:59:00: IGMP: Send v2 general Query on FastEthernet000:59:00: IGMP: Set report delay time to 7.0 seconds for 0 on FastEthernet000:59:07: IGMP: Send v2 Report for 0 on FastEthern

49、et000:59:07: IGMP: Received v2 Report on FastEthernet0 from for 000:59:07: IGMP: Received Group record for group 0, mode 2 fromfor 0sources00:59:07: IGMP: Updating EXCLUDE group timer for 000:59:16: PIM: Send v2 Hello on FastEthernet000:59:21: PIM: Send v2 Hello on Serial000:59:24: PIM: Received v2

50、Hello on Serial1 from 00:59:24: PIM: Received v2 Hello on Serial0 from 00:59:24: PIM: Hello packet has unknown option 20, ignored00:59:24: PIM: Send v2 Hello on Serial100:59:46: PIM: Send v2 Hello on FastEthernet000:59:51: PIM: Send v2 Hello on Serial000:59:54: PIM: Received v2 Hello on Serial1 from

51、 00:59:54: PIM: Received v2 Hello on Serial0 from 00:59:54: PIM: Hello packet has unknown option 20, ignored00:59:54: PIM: Send v2 Hello on Serial101:00:00: IGMP: Send v2 general Query on FastEthernet001:00:00: IGMP: Set report delay time to 8.4 seconds for 0 on FastEthernet001:00:09: IGMP: Send v2

52、Report for 0 on FastEthernet001:00:09: IGMP: Received v2 Report on FastEthernet0 from for 001:00:09: IGMP: Received Group record for group 0, mode 2 fromfor 0sources01:00:09: IGMP: Updating EXCLUDE group timer for 001:00:16: PIM: Send v2 Hello on FastEthernet001:00:21: PIM: Send v2 Hello on Serial00

53、1:00:24: PIM: Received v2 Hello on Serial1 from 01:00:24: PIM: Received v2 Hello on Serial0 from 01:00:24: PIM: Hello packet has unknown option 20, ignored01:00:24: PIM: Send v2 Hello on Serial101:00:24: PIM: Received v2 Assert on Serial0 from 01:00:24: PIM: Assert metric to source is 90/219801601:0

54、0:24: PIM: We lose, our metric 90/2051456001:00:24: PIM: Prune Serial0/34 from (/32, 34)01:00:24: PIM: (/32, 34) oif Serial0 in Prune state01:00:24: PIM: Received v2 Assert on Serial0 from 01:00:24: PIM: Assert metric to source is 90/219801601:00:24: PIM: We lose, our metric 90/2051456001:00:24: PIM: Prune Serial0/92 from (/32, 92)01:00:24: PIM: (/32, 92) oif Serial0 in Prune state01:00:25: PIM: Send v2 Prune on Serial1 t