iproute.se wrote: » If you have multiple routers in the same LAN (R1&R2) and your PC (H1) is sending non-local traffic to R1 which in turn sends it to R2 based on its routing table then it would be better off if your PC sent it directly to R2 therefor R1 will issue an ICMP redirect telling you to do so. This figure will you show an example
FrankGuthrie wrote: » So basically R2 has a shorter path?
iproute.se wrote: » Yes in this case, not a good design though. If you have redundant routers on your LAN you would like to have the same cost to any remote network to avoid this scenario. ICMP redirects is usually not something you would like to see.
iproute.se wrote: » To quote Richard Stevens "A common use for redirects is to let a host with minimal routing knowledge build up a better routing table over time. The host can start with only a default route (either R1 or R2 from our example in Figure 9.3) and anytime this default turns out to be wrong, it'll be informed by that default router with a redirect, allowing the host to update its routing table accordingly. ICMP redirects allow TCP/IP hosts to be dumb when it comes to routing, with all the intelligence in the routers. Obviously R1 and R2 in our example have to know more about the topology of the attached networks, but all the hosts attached to the LAN can start with a default route and learn more as they receive redirects."
FrankGuthrie wrote: » Thanks for the reply, but this example also looks like a non preferred scenario. I;m looking for a valid reason to use it.
