Re: Routing Suggestions

[Jon Lewis <jlewis () lewis org>]

On Thu, 13 Jan 2011, Adrian Chadd wrote:

> On Wed, Jan 12, 2011, Jon Lewis wrote:
> > On Wed, 12 Jan 2011, Jared Mauch wrote:
> >
> > > I suggest using one of the reserved/private BGP asns for this purpose.
> > >
> > > ASNumber:       64512 - 65535
> >
> > It sounds to me like Company B isn't doing BGP (probably has no experience
> > with it) and if there's only a single prefix per side of the cross
> > connect, especially if the cross connect is going into routers smart
> > enough to remove a route from the table if the destination interface is
> > down, static would do just fine.
>
> Unless you'd like to ensure the sensitive traffic doesn't cross an
> "unsafer" default rout path if the XC is down.

BGP would have that same issue since B is default routing to their 
provider.

[config for B]
ip route <A's prefix> <mask> <gw to A>
ip route <A's prefix> <mask> null0 250
ip route 0.0.0.0 0.0.0.0 <B's provider>

problem solved.  If the gw to A is reachable, traffic goes via the cross 
connect.  If the gw is down, traffic goes nowhere.

----------------------------------------------------------------------
 Jon Lewis, MCP :)           |  I route
 Senior Network Engineer     |  therefore you are
 Atlantic Net                |
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