[c-nsp] Redundant default route, without round-robin routing

[Oliver Boehmer (oboehmer)]

Vincent De Keyzer <> wrote on Thursday, September 27, 2007 6:46 PM:

> Thanks for the many replies.
> 
> To answer Tim's question: I don't really care, traffic can go to both
> A and B, or go to A and then B if A fails: what I care for is
> out-of-sequence packets.
> 
> Oliver's answer sounds reassuring - is it possible to obtain some
> evidence of this via a show command?

sure, "show ip cef 0.0.0.0 0.0.0.0" should show both paths, and
"per-destination sharing". see
http://www.cisco.com/en/US/products/hw/modules/ps2033/prod_technical_ref
erence09186a00800afeb7.html

> There is still one thing I don't understand:
> 
>> Make sure to mesh the two eBGP speakers via iBGP.
>> Guess you want to disable icmp redirects on the interface,
>> best link those two eBGP speakers with a dedicated link to
>> prevent blackholes..
> 
> ... disable icmp redirects on which interface exactly?

on the /27 interface linking all the routers together. Otherwise it
could happen that a node follows the default-route to A, but if A
doesn't know the destination via eBGP, but via iBGP from B, it will send
a redirect to the node. This could be undesireable..

	oli