NE40E-X8 mpls L3 vpn,有路由,带实例互ping不通.

发布时间:  2016-07-04 浏览次数:  428 下载次数:  0
问题描述

拓扑图如下:


组网描述:AS64512和AS64970通过optionB跨域VPN对接,AS64512域内RR入图中图标所示两个RR反射器同在一个反射簇。区域设备都直接与RR反射器建立IBGP邻居,并作为客户端(R6、R7为非客户端),IGP层为ospf协议链路cost值入图所示。AS64970域内RR反射器为两个ASBR设备,R13直接与出口R12建立IBGP邻居并作为客户端。

故障现象:R1和R13mpls L3 vpn,有路由,带实例互ping不通.

处理过程

<R1-NE40E_1>ping -vpn-instance FK1110-VPN 172.49.17.1
  PING 172.49.17.1: 56  data bytes, press CTRL_C to break
    Request time out
    Request time out
    Request time out
    Request time out
    Request time out

  --- 172.49.17.1 ping statistics ---
    5 packet(s) transmitted
    0 packet(s) received
    100.00% packet loss
ping对端地址不通,首先检查路由学习是否正常。

<R1-NE40E_1>dis ip routing-table vpn-instance  FK1110-VPN 172.49.17.1
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Table : FK1110-VPN
Summary Count : 1
Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface

    172.49.17.1/32  IBGP    255  0          RD   10.254.254.109  GigabitEthernet2/0/0
通过查找路由表发现路由学习正常,由于该路由是MPLS L3VPN路由,路由正常但是无法Ping通可能是标签分配不正
常导致,故通过检查需要检查LSP隧道是否正常。由于两个局点之间经过了option B跨域,而且对端设备无法登陆,
故逐段排查LSP隧道。

<R1-NE40E_1>tracert 10.254.254.109
traceroute to  10.254.254.109(10.254.254.109), max hops: 30 ,packet length: 40,press CTRL_C to break
1 10.254.254.4 32 ms  28 ms  27 ms
2 10.254.96.66 28 ms  34 ms  27 ms
3 10.254.99.66 34 ms  34 ms  33 ms
<R1-NE40E_1>tracert lsp  ip  10.254.254.109 32
  LSP Trace Route FEC: IPV4 PREFIX 10.254.254.109/32 , press CTRL_C to break.
  TTL   Replier            Time    Type      Downstream
  0                                Ingress   10.254.120.65/[3430 ]
  1     10.254.120.65      6 ms    Transit   10.254.96.66/[5645 ]
  2     10.254.96.66       31 ms   Transit   10.254.32.2/[6807 ]
  3     10.254.32.2        28 ms   Transit   10.254.99.66/[3 ]
  4     10.254.254.109     61 ms   Egress      

<R10-NE40EX8_2>tracert 10.254.120.126
traceroute to  10.254.120.126(10.254.120.126), max hops: 30 ,packet length: 40,press CTRL_C to break
1 10.254.99.65 3 ms  2 ms  2 ms
2 10.254.32.1 36 ms  2 ms  2 ms
3 10.254.254.4 33 ms  28 ms  28 ms
4 10.254.120.126 28 ms  28 ms  28 ms
<R10-NE40EX8_2>tracert lsp  ip  10.254.120.126 32
  LSP Trace Route FEC: IPV4 PREFIX 10.254.120.126/32 , press CTRL_C to break.
  TTL   Replier            Time    Type      Downstream
  0                                Ingress   10.254.99.65/[7443 ]
  1     10.254.99.65       10 ms   Transit   10.254.32.1/[6131 ]
  2     10.254.32.1        14 ms   Transit   10.254.96.65/[5042 ]
  3     10.254.96.65       39 ms   Transit   10.254.120.66/[3 ]
  4     10.254.120.126     32 ms   Egress      

通过tracert LSP可以发现AS64512域内LSP隧道建立正常,标签分发正常。故需要逐段排查具体对包位置。

根据ping报文流向清理割接口计数,结果显示如下(以某一接口示例):
<R1-NE40E_1>dis interface GigabitEthernet  2/0/0
Statistics last cleared:2016-07-04 15:02:44
    Last 300 seconds input rate: 14712 bits/sec, 7 packets/sec
    Last 300 seconds output rate: 11304 bits/sec, 6 packets/sec
    Input: 1043833 bytes, 4208 packets
    Output: 827595 bytes, 3425 packets
    Input:
      Unicast: 3912 packets, Multicast: 295 packets
      Broadcast: 1 packets, JumboOctets: 0 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 3160 packets, Multicast: 265 packets
      Broadcast: 0 packets, JumboOctets: 0 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overrun: 0 packets
      TxPause: 0 packets
      Unknown Vlan: 0 packets

ping1600字节的超长帧观看沿途设备接口下计数;
<R1-NE40E_1>ping -vpn-instance FK1110-VPN -s 1600 -m 100 -t 100 -c 100 172.49.17.1
  PING 172.49.17.1: 1600  data bytes, press CTRL_C to break
    Request time out
    Request time out
    Request time out
    Request time out

<R1-NE40E_1>dis interface GigabitEthernet  2/0/0                                  
    Last 300 seconds input rate: 14896 bits/sec, 8 packets/sec
    Last 300 seconds output rate: 15832 bits/sec, 7 packets/sec
    Input: 1142349 bytes, 4763 packets
    Output: 1084925 bytes, 4114 packets
    Input:
      Unicast: 4441 packets, Multicast: 321 packets
      Broadcast: 1 packets, JumboOctets: 0 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 3824 packets, Multicast: 290 packets
      Broadcast: 0 packets, JumboOctets: 100 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overrun: 0 packets
      TxPause: 0 packets
      Unknown Vlan: 0 packets

<R3-NE5000E_1>dis interface  GigabitEthernet  1/3/0
Statistics last cleared:2016-07-04 15:05:55
    Last 30 seconds input rate: 33875 bits/sec, 11 packets/sec
    Last 30 seconds output rate: 12516 bits/sec, 8 packets/sec
    Input: 939698 bytes, 3597 packets
    Output: 969396 bytes, 4105 packets
    Input:
      Unicast: 3349 packets, Multicast: 245 packets
      Broadcast: 0 packets, JumboOctets: 100 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 3828 packets, Multicast: 275 packets
      Broadcast: 0 packets, JumboOctets: 0 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overruns: 0 packets
      TxPause: 0 packets
    Local fault: normal, Remote fault: normal.


<R10-NE40EX8_2>dis interface GigabitEthernet  1/0/0           
Statistics last cleared:2016-07-04 15:10:41
    Last 30 seconds input rate: 16280 bits/sec, 20 packets/sec
    Last 30 seconds output rate: 104153640 bits/sec, 18852 packets/sec
    Input: 252522 bytes, 2479 packets
    Output: 4041500242 bytes, 6144871 packets
    Input:
      Unicast: 2342 packets, Multicast: 137 packets
      Broadcast: 0 packets, JumboOctets: 0 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 6144728 packets, Multicast: 143 packets
      Broadcast: 0 packets, JumboOctets: 0 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overrun: 0 packets
      TxPause: 0 packets
      Unknown Vlan: 0 packets
通过查看各接口下出入方向的JumboOctets报文计数可以发现报文,R10-NE40EX8_2入方向没有收到JumboOctets报文
,也即在经过H3C设备后为正常发送到R10-NE40EX8_2。在从R10-NE40EX8_2反ping查看结果。

<R1-NE40E_1>ping -vpn-instance FK1110-VPN -s 1600 -m 100 -t 100 -c 100 172.49.0.1
  PING 172.49.17.1: 1600  data bytes, press CTRL_C to break
    Request time out
    Request time out
    Request time out
    Request time out
<R10-NE40EX8_2>dis interface GigabitEthernet  1/0/0                                 
Statistics last cleared:2016-07-04 15:10:41
    Last 30 seconds input rate: 2728 bits/sec, 4 packets/sec
    Last 30 seconds output rate: 105903416 bits/sec, 20061 packets/sec
    Input: 298281 bytes, 3079 packets
    Output: 6073196616 bytes, 9144604 packets
    Input:
      Unicast: 2874 packets, Multicast: 205 packets
      Broadcast: 0 packets, JumboOctets: 0 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 9144391 packets, Multicast: 213 packets
      Broadcast: 0 packets, JumboOctets: 100 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overrun: 0 packets
      TxPause: 0 packets
      Unknown Vlan: 0 packets

<R3-NE5000E_1>dis interface  GigabitEthernet  1/3/0
Statistics last cleared:2016-07-04 15:05:55
    Last 30 seconds input rate: 10333 bits/sec, 4 packets/sec
    Last 30 seconds output rate: 37668 bits/sec, 9 packets/sec
    Input: 1185227 bytes, 4439 packets
    Output: 1432650 bytes, 5374 packets
    Input:
      Unicast: 4106 packets, Multicast: 330 packets
      Broadcast: 0 packets, JumboOctets: 100 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 4994 packets, Multicast: 374 packets
      Broadcast: 1 packets, JumboOctets: 100 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overruns: 0 packets
      TxPause: 0 packets
    Local fault: normal, Remote fault: normal.

<R1-NE40E_1>dis interface GigabitEthernet  2/0/0
Statistics last cleared:2016-07-04 15:02:44
    Last 300 seconds input rate: 16472 bits/sec, 7 packets/sec
    Last 300 seconds output rate: 14720 bits/sec, 6 packets/sec
    Input: 1664687 bytes, 6313 packets
    Output: 1381624 bytes, 5207 packets
    Input:
      Unicast: 5870 packets, Multicast: 441 packets
      Broadcast: 2 packets, JumboOctets: 100 packets
      CRC: 0 packets, Symbol: 0 packets
      Overrun: 0 packets, InRangeLength: 0 packets
      LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets
      Fragment: 0 packets, Undersized Frame: 0 packets
      RxPause: 0 packets
    Output:
      Unicast: 4815 packets, Multicast: 392 packets
      Broadcast: 0 packets, JumboOctets: 100 packets
      Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets
      System: 0 packets, Overrun: 0 packets
      TxPause: 0 packets
      Unknown Vlan: 0 packets
通过方向ping发现报文正常经过H3C设备,R1到R13的报文在出方向丢在了R9-SR8808_1设备上。故通过修改沿途cost值将沿途路径从SR8808设备绕过查看问题是否能够解决。此时路径如下图所示,并通过绕开SR8808设备后即能ping通对端设备,故最终确认根因为VPN报文丢在了H3C设备。



根因
报文发送到H3C设备上但是H3C设备没有发送出去
解决方案
修改现网Cost值将访问流量绕开H3C的SR8808设备后问题解决。

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