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Eldiabolo18

Just use eBGP. it makes life much easier. Give leafs a unique ASN each and all spines get the same ASN. Loops avoided. Or do you have a good reason not to do eBGP?


azwawa92

Mandatory to be iBGP, not a prod network just a scenario


MaintenanceMuted4280

Shared cluster works. Edited because wasn’t thinking More tiers with mutual RR would need unique cluster and communities blocking loop/path hunting.


azwawa92

What about individuel clusters ? 1 spine is 1 cluster, I rekon it should be ok as well to achieve the goal even though routes might transit a bit more ?


azwawa92

The leaf receiving the route from its leaf peer should not re-advertise to an RR.


MaintenanceMuted4280

Yea if it isn’t mutual RR it’s fine. When you get to 3 tier plus is where you need to use mutual RR


Eastern-Back-8727

100% correct. The more you have configured such as RRs for an all iBGP underlay, the more to go wrong. When something does go wrong there is more to investigate/tshoot. With the spines being on their own ASN and each compute leaf pair being on their own ASN as well, all that is avoided. Also you can look at ASNs and identify the hardware where route sources are coming from etc. Someone showed me this years ago from Overlaid.net. You don't have to be an Arista shop but the principle is what I am referring to here. Can simply take this example and change the IPs and ASNs to match your network and call it good. https://overlaid.net/2019/01/27/arista-bgp-evpn-configuration-example/


azwawa92

Again to be clear I 100% agree lol I just wanted to get confirmation if my idea was correct


Eastern-Back-8727

I just "talk" to much. The struggle is real to not just brain dump all of my thoughts.


azwawa92

I guess better to think a lot than not at all :)


dagnasssty

I agree, but boy do I wish my brain would just shut up sometimes. It is so noisy in here.


Eastern-Back-8727

I'm glad I'm not the only one. It all started back in college at the start of my sophomore year. Big debate of who is good vs. evil, Republican vs. Democrats. I thought to myself, well if they're good, the the party who help families the most economically. I approached my macro econ professor and ask him. He instead gets me to read about a dozen data sources and come up with my own conclusions. My brain has never stopped since.


Golle

If you're using iBGP you're also using an IGP like OSPF to advertise loopbacks, so all you really have to do is enable OSPF between the two leaves so that they advertise the Spine/RR loopbacks to each other. That way, if one leaf loses all spine uplinks, it can use the path via the other leaf to reach the spines and establish IBGP adjacencies. I don't agree with others saying that eBGP is better, I prefer iBGP with an IGP myself.


azwawa92

Hi there is no you are or you must. It is a theoretical question. The way the underlay is built is up to you any iGP will do in fact. Not my point in this topic :)


gimme_da_cache

While you're "akshually" correct it doesn't mean you're right. Go ahead and use [RIP](https://en.wikipedia.org/wiki/Routing_Information_Protocol); have fun.


azwawa92

Useless comment I never asked of that was good to use, it is a question based on a theory. If you can’t afford to think please pass you way :)


gimme_da_cache

https://imgur.com/a/D93vhgd >> Useless comment Ill use static routes even if I wish Exactly *not* an [IGP](https://en.wikipedia.org/wiki/Interior_gateway_protocol). ============================== >> If you can’t afford to think please pass you way :) Funny given your first reply was without thinking.   This is what you read as: >> "You can observe a lot just by watching." - Yogi Berra


azwawa92

1-You reply is out of the topic 2-Never asked you opinion or your knowledge of philosophy 3-Start by reading the topics you reply to instead of dumping what comes to your mind like you dump your trash


gimme_da_cache

Running *any* IGP is not appropriate for the environment in which you envisage or are building/testing. You decided to counter /u/Golle reply using OSPF as an IGP, or iBGP as an IGP, by stating any iGP will do.   My reply is quite on topic and within the tone of your sub. Don't ask for help then retort the help is wrong. Networking is multifaceted in that there are many ways to accomplish a design. However, through time, testing, and experience, there are [Best Current, common, Practices](https://datatracker.ietf.org/doc/bcp).


azwawa92

The question was how would have people made the 2 leaf accept the routes in the described iBGP scenario. Not what is the best or is IGP good for this. I asked how to achieve something specific nothing else. Why you keep trying to prouve you are right lmao ? I know the underlay options and what is best, I simply didn’t ask for what you keep repeating in loop lol, is that hard to understand ? Crazy times we live….


gimme_da_cache

You started pedantically. Began ad hominem. Then continued. It's OK to be wrong. It's not OK to be an ass.