Hi
Span isn't working on subinterfaces.
However, on ASR there is an embedded packet capture. You can export the capture in a pcap file and look at it from your PC or as well look at these traces directly on the router.
The minding is create and acl to match the traffic you want to analyze (Then you will be able to select your subinterface network as source/destination). Start the capture and export it.
I will not type all commands here as there are some good documentations:
- http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/epc/configuration/xe-16/epc-xe-16-book/nm-packet-capture-xe.html
- https://supportforums.cisco.com/document/139686/configuration-example-embedded-packet-capture-cisco-ios-and-ios-xe#Cisco_IOS-XE_Configuration_Example
If you need help, I will be able to help but following examples I think it will not be a big deal.
Thanks
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Thanks
Francesco
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