Lecture 2 - Static Routes Fundamentals

NOTE: This is a hub and spoke topology over FRAME RELAY, (R1 is the hub)

Lets see if we can ping the loopback interface of R2 from R3, no it fails,

I have enabled Debug IP packet (handy to use, but use WITH CAUTION lol)

We have no route to the network, lets fix that with a static route to R1 (as this is the hub)

Lets test the next hop address is reachable (R1 -123.1) yes i can [ping it, lets try R2's loopback

Ah, seen that before! looks like we are getting timeouts and unreachables .... WHY, because we know how to get to R1 (our next hop) but R1 does not know how to get to 2.2.2.2

IT IS NOT ENOUGH TO JUST CONFIGURE THE LOCAL ROUTER WITH STATIC ROUTING, YOU NEED TO ENSURE ALL DOWNSTREAM ROUTERS KNOW HOW TO GET TO THE NETWORK ALSO

Static routing peeps ..... gotta lurve it lol

To confirm, here is R1's routing table

Lets enable the debug on R3 again and confirm what is happening with the packets .....

So we can see the packets are now leaving R3, whereas before they were not (here is the debug on R1, notice the sending and receiving)

Can we ping R2's loopback interface ........ no

Lets get a static route configured here;

kooolio, sorted. notice the Source IP of 2.2.2.2 coming back to us... :0)

Also remember if RIP were running on the serial links, it would see this as 1 HOP away, same as the route over the ethernet segment and would load balance, if for the above reasons we would not want this to happen, so .....

Lets look at this on the next vid,