Based on my understanding on BFD, it will not help you... BFD will detect the direct connected port being down quicker and force the BGP session down, (faster than the time BGP session timers take to determine something is broken) This is the common issue / challenge in how to determine up-stream path outage and then doing appropriate route engineering on an automatic basis. Maybe a SLA monitor type scripting/configuration be useful in your case. Faisal Imtiaz Snappy Internet & Telecom 7266 SW 48 Street Miami, FL 33155 Tel: 305 663 5518 x 232 Help-desk: (305)663-5518 Option 2 or Email: Support@Snappytelecom.net ----- Original Message -----
From: "Olivier Benghozi" <olivier.benghozi@wifirst.fr> To: nanog@nanog.org Sent: Friday, February 7, 2014 5:25:53 AM Subject: Re: carrier comparison
Hi Faisal,
You might have to deploy some other means of (script ?) to bring your BGP session down from the 'broken' Service Provider.
To the best of my knowledge, BGP does not have any mechanism to determine broken connectivity upstream past the router you are BGP session is up with.
Well, technically there's BFD that might do the trick. But of course it won't be available; it's not usually, so specially with Cogent... :) But maybe its link was just overloaded in fact.
-- Olivier