Subject: [Idr] Large BGP Communities debugging tools (tcpdump, wireshark)

From: Job Snijders <[email-masked]>
Date: Wed, 12 Oct 2016 22:59:20 +0200

Dear implementers, working group.

To ease debugging your implementation of Large BGP Communities, the
toolchain has now been upgraded. For various flavours of tcpdump and
wireshark patches have been made available.

tcpdump.org is the upstream vendor for some of the Linux and BSD
distributions out there, they have committed support for decoding Large
BGP Communities into their master branch:

    https://github.com/the-tcpdump-group/tcpdump/issues/543
    (this this thread contains PCAP data suitable for tool testing,
    kindly provided by Pier Carlo Chiodi)

    https://github.com/the-tcpdump-group/tcpdump/commit/bc700c426251f8d93049d71fd4c007d22b2a2aa0

Wireshark is a populair and detailed packet tracer (also famous for
their CLI tool 'tshark'). Arjen Zonneveld submitted a patch to the
wireshark project:
    
    https://code.wireshark.org/review/#/c/18172/

A patch for FreeBSD's tcpdump is available:

    https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=213423

A patch for OpenBSD's tcpdump is available:

    http://marc.info/?l=openbsd-tech&m=147629067413734&w=2

Please note: not all of these patches have (yet) been accepted into the
projects respective main branches or releases. For instance, the patch
might not be compliant with the project's style guide.

However, for development or early adaptor debugging purposes, these
tools beat reading the wire and decoding it in your head.

Kind regards,

Job