三星EIGRP故障处理报告.docx

三星EIGRP故障处理报告一、 故障现象北京总部7204 IOS版本为：(C7200-ADVENTERPRISEK9-M), Version 12.4(6)T9硬件配置为：NAME: Chassis, DESCR: Cisco 7204VXR, 4-slot chassisPID: CISCO7204VXR , VID: N/A, SN: 36043182 NAME: NPE-G1 0, DESCR: Cisco 7200 Series Network Processing Engine NPE-G1PID: NPE-G1 , VID: V03 , SN: 35987369 NAME: disk2, DESCR: 128MB Compact Flash Disk for NPE-G1PID: MEM-NPE-G1-FLD128 , VID: N/A, SN: N/A NAME: module 1, DESCR: SerialPID: PA-8T-V35= , VID: N/A, SN: 29559483 NAME: module 2, DESCR: SerialPID: PA-8T-V35= , VID: N/A, SN: 27496815 NAME: module 3, DESCR: ATM WAN OC3 SMI Port AdaptorPID: PA-A3-OC3SMI= , VID: N/A, SN: JAE1018156QNAME: module 4, DESCR: ATM WAN OC3+ SMI Port AdaptorPID: PA-A6-OC3SMI= , VID: N/A, SN: JAE1245ZGUNNAME: Power Supply 0, DESCR: Cisco 7200 AC Power SupplyPID: PWR-7200-AC , VID: N/A, SN: N/A NAME: Power Supply 1, DESCR: Cisco 7200 AC Power SupplyPID: PWR-7200-AC , VID: N/A, SN: N/A 北京总部7204給出eigrp 提示如下：Dec 1 14:47:41: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.25) is down: retry limit exceededDec 1 14:47:45: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.25) is up: new adjacencyDec 1 14:47:46: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 6 (ATM4/0.21) is down: retry limit exceededDec 1 14:47:49: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 6 (ATM4/0.21) is up: new adjacencyDec 1 14:48:13: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.8) is down: retry limit exceededDec 1 14:48:14: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 4 (ATM4/0.15) is down: retry limit exceededDec 1 14:48:15: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.8) is up: new adjacencyDec 1 14:48:18: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 4 (ATM4/0.15) is up: new adjacencyDec 1 14:48:38: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.16) is down: retry limit exceededDec 1 14:48:39: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.7) is down: retry limit exceededDec 1 14:48:41: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.7) is up: new adjacencyDec 1 14:48:41: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.16) is up: new adjacencyDec 1 14:48:42: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.25) is down: retry limit exceededDec 1 14:48:43: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.11) is down: retry limit exceededDec 1 14:48:45: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 8 (ATM4/0.25) is up: new adjacencyDec 1 14:48:46: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 6 (ATM4/0.21) is down: retry limit exceededDec 1 14:48:47: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.11) is up: new adjacencyDec 1 14:48:50: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 6 (ATM4/0.21) is up: new adjacencyDec 1 14:49:16: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.8) is down: retry limit exceededDec 1 14:49:16: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor (ATM4/0.8) is up: new adjacencyDec 1 14:49:16: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 4 (ATM4/0.15) is down: retry limit exceededDec 1 14:49:19: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 4 (ATM4/0.15) is up: new adjacencyDec 1 14:49:25: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 109: Neighbor 0 (ATM4/0.18) is down: retry limit exceeded 二、 故障判断关于%DUAL-5-NBRCHANGE: retry limit exceededCisco給出的解释为： The local router sent an update, query, or reply, but did not receive an acknowledgment. Check Layer 1 (L1) and Layer 2 (L2) connectivity Cisco认为出现此类问题：本地路由器发送了 update ，query ，reply 等报文但没有收到邻居的ACK 。并认为此类问题需要检查物理链路或二层的连接性问题。三、 故障解决过程一、 首先从链路考虑，发现北京总部为ATM 155M 划分子接口为点到点，下端为fram-relay 链路。由此判断此链路为非直连链路。二、 考虑到链路为非直连链路，分析有可能组播传输上会有问题。故在eirp的路由进程中，互相配置邻居。配置之后，错误提示依然存在。三、 接下调整egirp 的hold-time和 bandwidth做低速链路保障。调整之后，错误提示依然出现。四、 调整思路，检查双方是否能收到组播数据包，写access-list 进行获取 Access-list 139 permit ip host host 0 经检查组播数据双方均可收到。至此排除组播问题。五、 通过debug eigrp packets 发现没有ACK 数据包发出。查看邻居状态：SEC_Acs_1_O#sh ip eigrp neighbors AT4/0.8IP-EIGRP neighbors for process 109H Address Interface Hold Uptime SRTT RTO Q Seq (sec) (ms) Cnt Num3 AT4/0.8 296 2d20h 48 288 15 19894在此来看几个关键参数：smooth round-trip time (SRTT)The number of milliseconds it takes for an EIGRP packet to be sent to this neighbor and for the local router to receive an acknowledgment of that packetRetransmission timeout (RTO), in millisecondsThe amount of time that the software waits before retransmitting a packet from the retransmission queue to a neighborQ countThe number of EIGRP packets (Update, Query, and Reply) that the software is waiting to send目前来看Q是15，也就是说 路由器发出Update, Query, and Reply，而下端路由器没有返回ACK。此处的传输使用单播。由此定位故障点。Cisco 給出此故障是layer 1 or layer 2 问题。/articles/article.asp?p=27839六、 通过检查，目前数据的单播通讯正常，端口无丢包和任何CRC 错误。由此可是，是路由协议的通讯出了问题，而路由协议通讯中不能正确识别，一般是由于数据进行了分片处理。查看接口：SEC_Acs_1_O#sh int atm4/0.8ATM4/0.8 is up, line protocol is up Hardware is ENHANCED ATM PA Plus Description: Internet address is /30 MTU 4470 bytes, BW 149760 Kbit, DLY 80 usec, reliability 255/255, txload 8/255, rxload 1/255 Encapsulation ATM 17632331 packets input, 6058317086 bytes 19419792 packets output, 11953447493 bytes 134260778 cells input, 258637285 cells output 194 OAM cells input, 184 OAM cells output AAL5 CRC errors : 0 AAL5 SAR Timeouts : 0 AAL5 Oversized SDUs : 0 Last clearing of show interface counters never对端：Nanning#sh int s0/2/0Serial0/2/0 is up, line protocol is up Hardware is GT96K Serial Description: Internet address is /30 MTU 1500 bytes, BW 2000 Kbit, DLY 20000 usec, reliability 255/255, txload 2/255, rxload 5/255 Encapsulation FRAME-RELAY IETF, loopback not set Keepalive set (10 sec) LMI enq sent 39442, LMI stat recvd 39442, LMI upd recvd 0, DTE LMI up LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0 LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE Broadcast queue 0/64, broadcasts sent/dropped 40623/0, interface broadcasts 28489 Last input 00:00:02, output 00:00:00, output hang never Last clearing of show interface counters 4d13h Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 95 Queueing strategy: weighted fair Output queue: 0/1000/64/95 (size/max total/threshold/drops) Conversations 0/100/256 (active/max active/max total