Re: BGP hold timer on IX LAN

[Nikolay Shopik <shopik () inblock ru>]

BFD is your friend. Yes it's require both parties to understand it but it much better than 30sec hold time. BIRD 
already have support for BFD

> On 27 окт. 2015 г., at 10:31, "marcel.duregards () yahoo fr" <marcel.duregards () yahoo fr> wrote:
>
> Hello,
>
> As all of us know BGP was designed for scalability, thus slow convergence. But it was also when CPU was slow :-).
>
> What do you think about the standard eBGP hold timer of 180sec ? Conservative ?
>
> I'm asking because we see more and more peering partners which force the hold timer to a lower value, and when BGP 
> negotiate the timer, the lowest hold timer is the winner.
>
> Shall we all decide that for global faster convergence we should ALL decrease the hold timer ? Or those guys which 
> are lowering their (and our) timers on IX LAN play a dangerous game ?
>
>
> See a example of our peering router at AMS-IX (hold from 30s to 180s):
>
>
> ......
> 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  interval is 60 seconds
>
> 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 interval is 30 seconds
>
> 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 interval is 60 seconds
>
> 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 interval is 10 seconds
>
> 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 interval is 60 seconds
>
> 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 interval is 60 seconds
>
> 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 interval is 30 seconds
>
> 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 interval is 30 seconds
>
> 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 interval is 60 seconds
>
> 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 interval is 60 seconds
>
> 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 interval is 10 seconds
>
> 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 interval is 30 seconds
>
> .....
>
>
> I've somehow basically anonymized ip and AS just in case I'm not allowed to publish those details.
>
>
> Best Regards,
> -Marcel