Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0

Jared Mauch <jared@puck.nether.net> Sat, 12 December 2020 18:24 UTC

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From: Jared Mauch <jared@puck.nether.net>
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Date: Sat, 12 Dec 2020 13:24:25 -0500
Cc: John Scudder <jgs=40juniper.net@dmarc.ietf.org>, idr@ietf.org
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To: Job Snijders <job@sobornost.net>
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Subject: Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0
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> On Dec 12, 2020, at 11:54 AM, Job Snijders <job@sobornost.net> wrote:
> 
> Sessions with broken peers are not torn down, which prevents much
> needed WITHDRAW messages from being generated.

Yeah but is this a protocol issue (BGP) or a transport implementation issue, or just a BGP implementation issue? We have mostly stopped using XR for a variety of issues and I'm happy to not be dealing with the transport bugs in 2020. I hope they clean up that stack soon, but given how long it's been I kinda a doubt it. 

I'm also sure the bugs aren't limited to a single vendor. Everyone's transport implementation will be different.