topic Re: BGP RIB out and Local RIB in General Topics

BGP RIB out and Local RIB

rajaram401 — Tue, 20 Jun 2017 15:01:49 GMT

Can someone explain me the difference between RIB out tab and Local RIB in BGP.

What is contained in RIB out and Local RIb?

Also what is pupose of Import and Export tab in BGP

Appreciate your help.

-Rajaram.

Re: BGP RIB out and Local RIB

acc6d0b3610eec313831f7900fdbd235 — Tue, 20 Jun 2017 17:49:14 GMT

Hi @rajaram401

What is contained in RIB out and Local RIb?

In the routing process, connections are established between BGP peers (or neighbors). If a route is permitted by the policy, it is stored in the routing information base (RIB). Each time the local firewall RIB is updated, the firewall determines the optimal routes and sends an update to the external RIB, if export is enabled.

What is pupose of Import and Export tab in BGP?

The import/export rules are used to import/export routes from/to other routers. For example, importing the default route from your Internet Service Provider.

I hope this helps.

Re: BGP RIB out and Local RIB

michaelmertens — Wed, 10 Jun 2020 19:22:51 GMT

So your explanation helps but I'm still fighting my way through my first BGP config, and I am learning BGP routes via two different eBGP peers (in different ASs) and I see those routes in my local RIB of router C. From those two eBGP speakers (router A & B); I appear to install routes in RIB out and see them in Router D for routes learned from router A, but I do not see in my RIB Out and routes from router B (which coincidentally is the only router announcing public addresses).

I do not have a Redistribute Profile (as I'm just routing between eBGB peers so I don't think I need one). For my Import, I'm importing a default route announced by router D and that works. I've trying creating an Export Rule to Router D, where the export rule is enabled, Match is undefined and Action is to Allow. However, those routes learned from Router B (public addresses) and are in Router C's local RIB are not in the RIB out (and are never seen in router D).

Admittedly, I'm totally confused whether Export/Import is needed in a particular router for simply propagating routes from one BGP speaker to another through.

Any clarity anyone could provide to me, well, would be amazing...Thanks!!!

Mike

Re: BGP RIB out and Local RIB

rmfalconer — Thu, 11 Jun 2020 15:11:28 GMT

Where does the PA fit in with all those routers?

I would recommend that you always have import and export filters, on routers or the PA. I always want to make sure I have control of route propagation on routers and firewalls instead of trusting others to do things correctly.

Re: BGP RIB out and Local RIB

michaelmertens — Fri, 12 Jun 2020 18:11:16 GMT

Yeah, my use of the term "router" was very poor- all four are PANs. I believe my issue was that I didn't have all the routes included in my Redistribute Rules or Redistribute Profile. I guess I'm still confused as to what the difference is. However, I've been enlightened to think of the Export and Import tabs as Cisco's Route Maps...

Thanks for piping in....

Mike