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Embedded packet Capture in router


This is regarding the new EPC feature available in Cisco routers for packet capture.

What is the maximum size of the buffer we can configure for packet capture. ?

Will the entire packets be stored or just the headers will be stored. Also if the interfcae is 100MB, normally if I use an external ethreal the packet capture will have around 300 MB.But in this case with router storing the packet in buffer, only very few packet details I can get.

AS the buffer will be occupying the memory of the router, will it have an impact on the router perfomance ?

Please confirm whether my below understanding is right.

1)if I am using linear buffer, once the buffer is full, it will discard the packets .

2)If I am using circular buffer, the packets will be added in a circular manner, overwriting existing packets and hence the buffer will contain the latest packets.

Please let me know to what extend this packet capture feature in router is useful.

Please also provide a url containing complete details of this new feature.

Thanks & Regards,


Re: Embedded packet Capture in router

1. Since EPC uses the volitile memory (DRAM) you are limited to the free space not used by the running image and configured protocols.

2. Yes, it will impact the router if memory is needed for addtional functions.

1) yes

2) yes

Its useful because you dont have to have any semi trained eyes on site.

URL ? You see that search bar in the top right hand corner ? Type in ECP IOS ISR and you'll get more than you can digest.