Ask the Expert: Packet Capture Capabilities of Cisco Routers and Switches

Question

With Rahul Rammanohar 
Welcome to the Cisco Support Community Ask the Expert conversation. This is an opportunity to learn and ask questions about packet capture capabilities of Cisco routers and switches.
In May 2013, we created a video that included packet capture capabilities across multiple Cisco routers and switches. For each product, we began with a discussion about the theory of the capabilities, followed by an explanation of the commands, and we concluded with a demo on real devices. In this Ask the Expert event, you’re encouraged to ask questions about the packet capture capabilities of these Cisco devices:
•       7600/6500: mini protocol analyzer (MPA), ELAM, and Netdr
•       ASR9k: network processor capture
•       7200/ISRs: embedded packet capture
•       Cisco Nexus 7K, 5K, and 3K: Ethanalyzer
•       Cisco Nexus 7K: ELAM
•       CRS: show captured packets
•       ASR1K: embedded packet capture
More Information
Blog URL: Packet Capture Capabilities of Cisco Routers and Switches
Watch the Video:  https://supportforums.cisco.com/videos/6226
Hitesh Kumar is a customer support engineer in the High-Touch Technical Services team at Cisco specializing in routing protocols. He has been supporting major service providers and enterprise customers in routing, Multiprotocol Label Switching (MPLS), multicast, and Layer 2 VPN (L2VPN) issues on routing platforms for more than three years. He has more than six years of experience in the IT industry and holds a CCIE certification (number 38757) in service. 
Rahul Rammanohar is a technical leader with the High-Touch Technical Support Team in India. He handles escalations in the area of routing protocols and large-scale architectures for devices running Cisco IOS, IOS-XR, and IOS-XE Software. He has been supporting major service providers and large enterprise customers for routing, MPLS, multicast, and L2VPN issues on all routing platforms. He has more than 13 years of experience and holds a CCIE certification (number 13015) in routing/switching and service provider.
Remember to use the rating system to let Hitesh and Rahul know if you have received an adequate response.  
Because of the volume expected during this event, Hitesh and Rahul might not be able to answer each question. Remember that you can continue the conversation in the Service Provider, sub-community forum shortly after the event. This event lasts through November 1, 2013. Visit this forum often to view responses to your questions and the questions of other Cisco Support Community members.

Answer 1

Hello Erick
    Thanks for the topology. The trigger will be different for labelled  packet as you would need to mention the values of labels too in the  trigger.
     Below are two examples of one or two labels being  used, it depends on where you are capturing the packet in mplsvpn  scenario which will decide teh number of labels being imposed on the  packet.
Trigger for one label. (if the router on which you are capturing the packet PHP is being performed)
VPN label - 5678
Source Address - 111.111.111.111
Destination Address - 123.123.123.123
show platform capture elam trigger dbus others if data = 0 0 0 0x88470162 0xE0000000 0 0 0x00006F6F 0x6F6F 7B7B 0x7B7B0000 [ 0 0 0 0xffffffff 0xf0000000 0 0 0x0000ffff 0xffffffff 0xffff0000 ]
Trigger for two labels. (for other core routers)
IGP label - 1234
VPN label - 5678
Source Address - 111.111.111.111
Destination Address - 123.123.123.123
show platform capture elam trigger dbus others if data = 0 0 0 0x8847004D 0x20000162 0xE0000000 0 0 0x00006F6F 0x6F6F7B7B 0x7B7B0000 [ 0 0 0 0xffffffff 0xf000ffff 0xf0000000 0 0 0x0000ffff 0xffffffff 0xffff0000 ]
    You can check the labels being used (by using show ip cef <> details) and covert their values to hex and change the trigger accordingly.
     I have changed the colors for better understanding. If you notice carefully in the trigger the values for ip address, labels have just been converted to their respective hex values which could be replaced.
     Please let me know if this helps.
Thanks & Regards
Hitesh & Rahul