[185535] in North American Network Operators' Group
Re: BGP hold timer on IX LAN
daemon@ATHENA.MIT.EDU (Nikolay Shopik)
Tue Oct 27 03:57:07 2015
X-Original-To: nanog@nanog.org
From: Nikolay Shopik <shopik@inblock.ru>
In-Reply-To: <562F2855.3060603@yahoo.fr>
Date: Tue, 27 Oct 2015 10:57:00 +0300
To: "marcel.duregards@yahoo.fr" <marcel.duregards@yahoo.fr>
Cc: North American Network Operators' Group <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
BFD is your friend. Yes it's require both parties to understand it but it mu=
ch better than 30sec hold time. BIRD already have support for BFD
> On 27 =CF=CB=D4. 2015 =C7., at 10:31, "marcel.duregards@yahoo.fr" <marcel.=
duregards@yahoo.fr> wrote:
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> Hello,
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> As all of us know BGP was designed for scalability, thus slow convergence.=
But it was also when CPU was slow :-).
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> What do you think about the standard eBGP hold timer of 180sec ? Conservat=
ive ?
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> I'm asking because we see more and more peering partners which force the h=
old timer to a lower value, and when BGP negotiate the timer, the lowest hol=
d timer is the winner.
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> Shall we all decide that for global faster convergence we should ALL decre=
ase the hold timer ? Or those guys which are lowering their (and our) timers=
on IX LAN play a dangerous game ?
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> See a example of our peering router at AMS-IX (hold from 30s to 180s):
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> ......
> BGP neighbor is 193.239.116.13x, remote AS 12x54, external link
> Last read 00:00:42, last write 00:00:13, hold time is 180, keepalive int=
erval is 60 seconds
>=20
> BGP neighbor is 193.239.116.13x, remote AS 31x77, external link
> Last read 00:00:09, last write 00:00:03, hold time is 90, keepalive inter=
val is 30 seconds
>=20
> BGP neighbor is 193.239.116.13x, remote AS 4x562, external link
> Last read 00:00:30, last write 00:00:07, hold time is 180, keepalive inte=
rval is 60 seconds
>=20
> BGP neighbor is 193.239.116.14x, remote AS 4x350, external link
> Last read 00:00:01, last write 00:00:01, hold time is 30, keepalive inter=
val is 10 seconds
>=20
> BGP neighbor is 193.239.116.14x, remote AS 341x1, external link
> Last read 00:00:09, last write 00:00:27, hold time is 180, keepalive inte=
rval is 60 seconds
>=20
> BGP neighbor is 193.239.116.14x, remote AS 2x028, external link
> Last read 00:00:00, last write 00:00:21, hold time is 180, keepalive inte=
rval is 60 seconds
>=20
> BGP neighbor is 193.239.116.15x, remote AS 41x52, external link
> Last read 00:00:27, last write 00:00:11, hold time is 90, keepalive inter=
val is 30 seconds
>=20
> BGP neighbor is 193.239.116.18x, remote AS 1x041, external link
> Last read 00:00:20, last write 00:00:14, hold time is 90, keepalive inter=
val is 30 seconds
>=20
> BGP neighbor is 193.239.116.18x, remote AS 162x8, external link
> Last read 00:00:28, last write 00:00:06, hold time is 180, keepalive inte=
rval is 60 seconds
>=20
> BGP neighbor is 193.239.116.20x, remote AS 47x86, external link
> Last read 00:00:59, last write 00:00:21, hold time is 180, keepalive inte=
rval is 60 seconds
>=20
> BGP neighbor is 193.239.116.21x, remote AS x3350, external link
> Last read 00:00:02, last write 00:00:01, hold time is 30, keepalive inter=
val is 10 seconds
>=20
> BGP neighbor is 193.239.116.24x, remote AS x5133, external link
> Last read 00:00:24, last write 00:00:03, hold time is 90, keepalive inter=
val is 30 seconds
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> .....
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> I've somehow basically anonymized ip and AS just in case I'm not allowed t=
o publish those details.
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>=20
> Best Regards,
> -Marcel
