We have customers in the same way you do. We only use Cisco (both pop routers and managed cpe) and use
neighbor xxx.xxx.xxx.xxx timers 5 15 on the pop routers with great success. We haven't found any drawback so far. // OK On Sat, May 23, 2009 at 12:45 AM, Steve Bertrand <[email protected]> wrote: > Hi all, > > I've got numerous single-site 100Mb fibre clients who have backup SDSL > links to my PoP. The two services terminate on separate > distribution/access routers. > > The CPE that peers to my fibre router sets a community, and my end sets > the pref to 150 based on it. The CPE also sets a higher pref for > prefixes from the fibre router. The SDSL router to CPE leaves the > default preference in place. Both of my PE gear sends default-originate > to the CPE. There is (generally) no traffic that should ever be on the > SDSL link while the fibre is up. > > Both of the PE routers then advertise the learnt client route up into > the core: > > *>i208.70.107.128/28 > 172.16.104.22 0 150 0 64762 i > * i 172.16.104.23 0 100 0 64762 i > > My problem is the noticeable delay for switchover when the fibre happens > to go down (God forbid). > > I would like to know if BGP timer adjustment is the way to adjust this, > or if there is a better/different way. It's fair to say that the fibre > doesn't 'flap'. Based on operational experience, if there is a problem > with the fibre network, it's down for the count. > > While I'm at it, I've got another couple of questions: > > - whatever technique you might recommend to reduce the convergence > throughout the network, can the same principles be applied to iBGP as well? > > - if I need to down core2, what is the quickest and easiest way to > ensure that all gear connected to the cores will *quickly* switch to > preferring core1? > > Steve > >
