[c-nsp] Next step-up from 7206VXR

[Nick Hilliard]

On 20/02/2013 09:49, Mack McBride wrote:
> Sup720 handles the average churn fine.  Spikes in churn can be an issue,
> but for the average use they are fine.
> The usual cause of spikes are full feed failures and re-convergence.

You have to be careful about this; there are some situations where using a
sup720 is not operationally sensible.  E.g. connecting to one of the larger
IXPs where it is no longer possible for a sup720 box to return to service
unaided after an IXP flap due to churn causing bgp session timeout +
teardown, causing more bgp churn, causing more teardown, etc

At the moment, the sup720 take about 5-6 minutes to handle a single dfz bgp
feed.  At 3 full feeds (e.g. transit + 2 x RR), this goes up to about 20
minutes before everything has settled (archive note: currently ~435000 dfz
prefixes).

Nick