Re: [Idr] new thread regarding capabilities handling

Enke Chen <> Thu, 27 April 2017 17:25 UTC

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To: Robert Raszuk <>
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Cc: Mikael Abrahamsson <>, idr wg <>, Enke Chen <>
From: Enke Chen <>
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Date: Thu, 27 Apr 2017 10:22:27 -0700
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Subject: Re: [Idr] new thread regarding capabilities handling
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Certainly with GR, the need for "Dynamic Capability" is significantly reduced.

Thanks.  -- Enke

On 4/27/17 6:44 AM, Robert Raszuk wrote:
>     What's the back story here? This is obviously a well-known understood problem then for 16 years already, why don't we still have this in 2017?
> ​Since you asked :) ....
> 1. Actually number of customers asked for it various vendors however non of them showed sufficient money so naturally features which are not associated with significant revenue are not that high on anyone's list (unless BGP code you are maintaining is your hobby). 
> 2. If we talking intra-domian in most cases ​you go via RRs. And it is a good practice to configure your RR side either with multiple loopbacks or even different contexts for each address family so each SAFI is independent from one another. That way within your domain you can add/delete AFI/SAFIs without impacting others. Moreover in case of using multiple context (VMs or LXCs for reflection) you get multithreading across SAFIs for free too. 
> 3. And last in general what really matters is to continue forwarding packets and not to impact your other peers by BGP session reset. And here comes quite well supported feature BGP Graceful Restart (RFC4724) It is applicable for both iBGP and eBGP peers. And honestly many networks still do not have it enabled even though it has been shipping for long time in most major BGP code basis. 
> Kind regards,
> Robert.