[Babel-users] a better bird config and a survived gnarly rtod test

[Dave Taht]

After the initial announcement, with exactly equivalent metrics,
routes should settle on the first one to announce, yes.

However several things will permute that. The first one is the random
order of reannounced routes from the labgw side...

The second one, is the "late hello" problem that happens when you run
low on cpu or bandwidth at large numbers of routes in rtod. Part of my
sekret plan is to observe how well the different implementations
perform in my usual
all-up-test-and-break-everything-so-badly-it-takes-months-to-sort-out-what-really-happened-while-giving-juliusz-major-heartburn
method.

(it would be good if bird and FRR could log late hellos).

And then of course, there just would be whatever normal breakage
happens. For example, I seem to recall that bird does not do ae
compression, thus it's packets will be larger, and slower on and off
the wire.....

another goal is come up with an exact equivalent config for
bird/frr/babeld for both ubuntu 18 and openwrt.

I remember the good ole days when we used to get dozens of people in
the same room to test interop, when, heck, the interop conference was
big, bugs were huge, and open source code, small....

Hmmm.... David? Got a binary for osx I could throw in the mix?

On 10/25/18, Toke Høiland-Jørgensen <toke at toke.dk> wrote:
> Dave Taht <dave.taht at gmail.com> writes:
>
>> does bird's metric 128 inflate that default metric then?
>
> The config with the 128 metric adds that to the initial metric, before
> the routes are announced the first time...
>
>> should it just be 0? 96?
>
> Well, that would depend on which policy you want to implement :)
>
>> Perhaps it would help if I shared my sekret plan.
>>
>> In the lab I have 3 routers for test purposes (7 actually, but...)
>>
>> labgw -------------------------------------------------- campusgw
>> (heavily filtered, I'm crazy but not entirely so)
>>               |                 |                      |
>>          FRR Router   BIRD router     BABELD router
>>               |                 |                      |
>>          ----------------a switch
>> -------------------------------------------
>>              |    |       |             |            |
>>   |
>>             a  bunch of          devices configured differently
>>
>> The routers are apu2s, the devices a misc collection of hackerboards,
>> with kernels
>> going back as far as 3.10.
>>
>> assuming all these do the right/same things with metrics, my
>> assumption is the firstmost router  to make an announcement will win.
>> apu2s also have two ports, so each has yet
>> another device hanging off of that...
>
> Hmm, yeah, if they all announce the same routes with the same metrics, I
> guess the devices will pick whichever one it establishes contact with
> first, and not switch that route over unless something changes...
>
> -Toke
>


-- 

Dave Täht
CTO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-831-205-9740