Redundant static routes


#1

I’m not sure if this is supposed to work, but I have the setup the text book example of three routers in a triangle.

I have R1 up top, Eth1 is the default gateway and where my terminal is in. Eth0 goes to R2 Eth0. Eth2 goes to R3 Eth0.

R2 and R3 are connected via their respective Eth1 interfaces.

I had static routes which let me get from each router to every other interface.
I added a second static route to R1 to get to the subnet between R2 and R3, I have the route a distance of 2 (also tried 10, and 100).

I assumed that this would be all that is required for redundancy, and if the initial route goes down the second one with higher distance would take over, however, nothing happens when I disable the relevant interfaces and traffic flow stops. I noticed that if I disabled the interface on R2, the port on R1 would still say u/u (unsure if that is normal). If I disable the port on R1 then do ‘show ip route’ I get ‘10.0.23.0/24 [1/0] via 10.0.13.3 (recursive via 172.21.153.1)’ That IP address is the default gateway.

R1 show ip route:
S>* 0.0.0.0/0 [210/0] via 172.21.153.1, eth1
C>* 10.0.12.0/24 is directly connected, eth0
C>* 10.0.13.0/24 is directly connected, eth2
S 10.0.23.0/24 [2/0] via 10.0.12.2
S>* 10.0.23.0/24 [1/0] via 10.0.13.3, eth2
C>* 127.0.0.0/8 is directly connected, lo
C>* 172.21.153.0/24 is directly connected, eth1

R1 show int eth:
Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
Interface IP Address S/L Description


eth0 10.0.12.1/24 u/u
eth1 172.21.153.159/24 u/u WAN
eth2 10.0.13.1/24 A/D

Eth2 shows A/D when I have disabled it, but it shows u/u if I disable the port on the other end (R2 Eth0)

I’m completely new to Vyatta/VyOS, I found a similar post from some years ago but there doesn’t appear to be an answer.

Cheers


#4

I think the problem is solved, disabling the port is not sufficient to cause a reroute. Using VirtualBox I instead disconnected the cable in the network options. Using this method, 19 pings were dropped before the network converged. 19 seems reasonable for RIP with default timers.

On this though, should disabling a port cause a reroute? I would think it a very handy thing to do when working remotely, how else would you test functionality?