A perl script to convert Cisco IOS/Nexus/ASA configurations to HTML for easier comprehension

Lee ler762 at gmail.com
Thu Oct 6 21:33:28 UTC 2016

On 10/6/16, Jesse McGraw <jlmcgraw at gmail.com> wrote:
> Nanog,
>      (This is me scratching an itch of my own and hoping that sharing it
> might be useful to others on this list.  Apologies if it isn't)
>    When I'm trying to comprehend a new or complicated Cisco router,
> switch or firewall configuration an old pet-peeve of mine is how
> needlessly difficult it is to follow deeply nested logic in route-maps,
> ACLs, QoS policy-maps etc etc
> To make this a bit simpler I’ve been working on a perl script to convert
> these text-based configuration files into HTML with links between the
> different elements (e.g. To an access-list from the interface where it’s
> applied, from policy-maps to class-maps etc), hopefully making it easier
> to to follow the chain of logic via clicking links and using the forward
> and back buttons in your browser to go back and forth between command
> and referenced list.
> I've put the script itself up here
> <https://github.com/jlmcgraw/network_configuration_navigator>:
> https://github.com/jlmcgraw/network_configuration_navigator
> See here
> <ttp://htmlpreview.github.com/?https://github.com/jlmcgraw/network_configuration_navigator/blob/master/examples/html_test_case_1.cfg.html>
> for output examples
> http://htmlpreview.github.com/?https://github.com/jlmcgraw/network_configuration_navigator/blob/master/examples/html_test_case_1.cfg.html
> Here's a quick web demo <https://hidden-waters-8218.herokuapp.com/> on
> Heroku
> https://hidden-waters-8218.herokuapp.com/
>      (This is just a simple web front-end to the script.  I'm not a
> web-savvy guy so I'm sure it's poorly coded and terribly insecure.
>      Please don't upload anything sensitive to this, it's just for
> testing!)
> I know there is a lot of stuff that could be done better so let me know
> if you think of anything new or notice something I’ve done wrong.
> One unexpected thing that has come out of this script is the ability to
> catch items that are defined but never actually used, whether it's due
> to a fat-finger or just being leftover cruft. This has proven very
> valuable in catching mistakes that are otherwise hard to spot.
> Unfortunately the script can't currently catch the inverse (things that
> are called but never defined) due to the way the regexes are constructed
> Surely this has all been done before but I couldn't find anything in a
> few brief moments of searching so here we are.

dunno about creating web pages, but
has a section on showing filters that are defined but not referenced &
referenced but not defined


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