[c-nsp] IOS-XR BGP RR MCID (Multiple Cluster ID)

[adamv0025 at netconsultings.com]

Hmm well ok, I guess if you have one set of static routes on RR1 and one set of static routes/loopback on RR2 –then sure you might want to use iBGP session between RR1 and RR2 for redundancy purposes (if say the particular RR1 is the only place you originate the given route from)

–but why not originating the same set of static routes/loopbacks out of both RRs in this case?

 

I mean in your case with common Cluster-ID on both RR1 and RR2 these odd per-RR routes are the only thing exchanged over that iBGP session anyways right?  

 

adam

 

netconsultings.com

::carrier-class solutions for the telecommunications industry::

 

From: Mark Tinka [mailto:mark.tinka at seacom.mu] 
Sent: Monday, March 12, 2018 2:31 PM
To: adamv0025 at netconsultings.com; 'Job Snijders'
Cc: 'Cisco Network Service Providers'
Subject: Re: [c-nsp] IOS-XR BGP RR MCID (Multiple Cluster ID)

 

 

On 12/Mar/18 12:34, adamv0025 at netconsultings.com <mailto:adamv0025 at netconsultings.com>  wrote:

The only scenario I can think of is if your two RRs say RR1 and RR2 in a POP 

serving a set of clients (by definition a cluster btw) -if these two RRs
have an iBGP session to each other - which is a big NONO when you are using
out of band RRs, no seriously. 


Why is it a big no-no?

We run iBGP sessions between our RR's within and outside of a cluster. No issues. It's useful for the RR's to learn, from each other, which routes they are originating, regardless of which cluster they may belong to.

And yes, these are out-of-path RR's.

Mark.