Cisco3945 MPLS L2VPN packet capture

[jerry.z.fan]

Hi,

I want to capture packet on gi0/0 of PE1 in  order to show customer that all his traffic is encapsulated and  transmitted by L2VPN (ldp signaling) in his lab.

CE1-----------(g0/1)PE1(g0/0)------------PE2-----------CE2

PE1 and PE2 are Cisco3945 and L2VPN is working well. I  tried cisco RITE(Router IP Traffic Export Packet Capture) feature, but  the output was not what I expected. I tried both export mode and capture  mode. Only LDP hello message I got, looks like RITE is only interested  in IP packet. Monitor session wasn't effective as well because it is not  a switch.

Is there any other way/workaround to capture customer's traffic encapsulated in L2VPN?

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What I did on PE1 when I was trying RITE export mode:

ip traffic-export profile test

bidirectional

interface GigabitEthernet0/2

mac-address e411.5b44.3a6d

interface GigabitEthernet0/2

ip address 10.1.2.1 255.255.255.0

interface GigabitEthernet0/0

ip traffic-export apply test

Gi0/2 connected my PC(10.1.2.2) with wireshark installed.

---------------------------------------------------------------

Many thanks.

Regards,

Jerry Fan

[Raju Sekharan]

I don't think there is any packet capturing mechanism availble in cisco routers to captue MPLS packet

You can connect a switch in middle of PE1 and PE2 and sniff the packets

Thank you

Raju

[Javier Portuguez]

Hi Jerry,

I agree with Raju.

Catalyst Switched Port Analyzer (SPAN) Configuration Example

HTH.

Please rate any helpful posts

[jerry.z.fan]

Many thanks, all. I originally don't want to use switch, so that can show my "powerful technical skill". Ahah. But.........

As another expert suggested, I tried another way 'monitor capture' today, but  failed. 'monitor capture' is only interested in ipv4 and ipv6. Maybe the  IOS in Cisco3945 isn't same as the IOS in Cat6500 or Cisco7600 or  GSR/CSR.

See following:

===================================================================

Router_MPS_TEST_A#monitor capture ?    

  buffer  Control Capture Buffers

  point   Control Capture Points

Router_MPS_TEST_A#monitor capture po

Router_MPS_TEST_A#monitor capture point ?

  associate     Associate capture point with capture buffer

  disassociate  Dis-associate capture point from capture buffer

  ip            IPv4

  ipv6          IPv6

  start         Enable Capture Point

  stop          Disable Capture Point

Router_MPS_TEST_A#monitor capture point ip ?

  cef               IPv4 CEF

  process-switched  Process switched packets

Router_MPS_TEST_A#monitor capture point ip p

Router_MPS_TEST_A#monitor capture point ip process-switched ?

  WORD  Name of the Capture Point

Router_MPS_TEST_A#monitor capture point ip process-switched test-point ?

  both     Inbound and outbound and packets

  from-us  Packets originating locally

  in       Inbound packets

  out      Outbound packets

Router_MPS_TEST_A#monitor capture point ip process-switched test-point b

Router_MPS_TEST_A#monitor capture point ip process-switched test-point both ?

Router_MPS_TEST_A#monitor capture point ip process-switched test-point both

===================================================================

At  last, I had to insert a switch in the middle of two cisco3945 and  configured port span. That worked very well.

Jerry Fan