Large prefix lists/sets on IOS-XR

Saku Ytti saku at
Sat Dec 10 06:47:21 UTC 2022

On Fri, 9 Dec 2022 at 20:19, tim at <tim at> wrote:

Hey Tim,

> Or at least, you've moved the problem from "generate config" to "have complete and correct data".  Which statement should probably come with some kind of trigger-warning...

I think it's a lot easier than you think. I understand that all older
networks and practical access networks have this problem, the data is
in the network, it's of course not the right way to do it, but it's
the way they are. But there is no reason to get discouraged.
First you gotta ignore waterfall model, you can never order something
ready and have utility out of it, because no data.

What you can do, day1

a) copy configs as-is, as templates
b) only edit the template
c) push templates to network

boom, now you are FAR, and that took an hour or day depending on the person.

Maybe you feel like you've not accomplished much, but you have. Now
you can start modelling data out of the template into the database,
and keep shrinking the 'blobs'.  You can do this at whatever pace is
convenient, and you can trivially measure which one to do next, which
one will reduce total blob bytes most.  You will see constant,
measurable progress. And you always know the network state is always
what is in your files, as you are now always replacing the entire
config with the generated config.


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