[j-nsp] Best practice for igp/bgp metrics

[Saku Ytti]

How different the bandwidth topology ends up being to strict hop-count
topology? How many changes would you need in hop-count topology to
make it same?

What I'm trying to say, if the bandwidth topology works, probably just
static number would work, as options between two nodes are all
reasonable. That is, either it is useless complexity but works
regardless or it does not work.



On 26 October 2017 at 02:14, Luis Balbinot <luis at luisbalbinot.com> wrote:
> Well, for the 99% of us that only do basic stuff with a TE tunnel every now
> and then that works fine. For those that have extremely demanding customers
> and critical services you will need  some sort of external controller to
> manage all that anyway and then we are basically replaced by scripts ;-)
>
> Luis
>
> On Wed, 25 Oct 2017 at 18:07 Saku Ytti <saku at ytti.fi> wrote:
>
>> Hey,
>>
>> This only matters if you are letting system assign metric
>> automatically based on bandwidth. Whole notion of preferring
>> interfaces with most bandwidth is fundamentally broken. If you are
>> using this design, you might as well assign same number to every
>> interface and use strict hop count.
>>
>> On 25 October 2017 at 22:41, Luis Balbinot <luis at luisbalbinot.com> wrote:
>> > Never underestimate your reference-bandwidth!
>> >
>> > We recently set all our routers to 1000g (1 Tbps) and it was not a
>> > trivial task. And now I feel like I'm going to regret that in a couple
>> > years. Even if you work with smaller circuits, having larger numbers
>> > will give you more range to play around.
>> >
>> > Luis
>> >
>> > On Tue, Oct 24, 2017 at 8:50 AM, Alexander Dube <nsp at layerwerks.net>
>> wrote:
>> >> Hello,
>> >>
>> >> we're redesigning our backbone with multiple datacenters and pops
>> currently and looking for a best practice or a recommendation for
>> configuring the metrics.
>> >> What we have for now is a full meshed backbone with underlaying isis.
>> IBGP exports routes without any metric. LSP are in loose mode and are using
>> isis metric for path calculation.
>> >>
>> >> Do you have a recommendation for metrics/te ( isis and bgp ) to have
>> some values like path lengh ( kilometers ), bandwidth, maybe latency, etc
>> inside of path calculation?
>> >>
>> >> Kind regards
>> >> Alex
>> >> _______________________________________________
>> >> juniper-nsp mailing list juniper-nsp at puck.nether.net
>> >> https://puck.nether.net/mailman/listinfo/juniper-nsp
>> > _______________________________________________
>> > juniper-nsp mailing list juniper-nsp at puck.nether.net
>> > https://puck.nether.net/mailman/listinfo/juniper-nsp
>>
>>
>>
>> --
>>   ++ytti
>>
> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp



-- 
  ++ytti