LAN - Route

[Matteo Guglielmi]

Connected to the LAN of my asus router (which is mainly used as a firewall) I have 3 cisco routers (RT1, RT2 and RT3) running eigrp. On the asus router I've defined a static route with default metric to RT1 and two more static routes to RT2 and RT3 with metric 10 and 20 respectively. The 3 static routes share the same summarized network since all cisco routers (RT1, RT2, and RT3) are connected to the same internal networks. The problem arises when I turn off RT1. In fact, I cannot reach anymore the management interface of the asus router on the LAN. To me it seems that the asus router keeps trying to send packages to RT1. As soon as I remove the static route to RT1, I can access again the asus router's management interface via the remaining static routes.

So, my question is:

is there any way to dynamically add or remove static routes on the asus router based on pingable ip addresses?

Also, how's the metric value used in the routing table?

Thank you.

### admin@BRTO3:/tmp/home/root# route ###

10.16.0.0 10.16.130.252 255.252.0.0 UG 1 0 0 br0
10.16.0.0 10.16.130.254 255.252.0.0 UG 11 0 0 br0
10.16.0.0 10.16.130.253 255.252.0.0 UG 21 0 0 br0

 

[ApexRon]

I have been away from Cisco routers for too long but I seem to remember that in an environment like yours there was a way to configure the Cisco routers with the same 'virtual' IP address say 10.16.130.250 while their real IP addresses were 252, 253,254. Should the Cisco router with the active 250 become inactive then another Cisco router would take over the 250 address.

I Googled what I am talking about and it is called Hot Standby Router Protocol (HSRP). If this is a valid option for you then only one static route would be needed in the ASUS.

 

[coxhaus]

Your problem is the ASUS does not support eigrp. So I think your problem is related to your default gateway or gateway of last resort and how you have it set up with eigrp. You only can setup 1 link with the ASUS using default routes. There is no path to the other routers other than the primary router.

As stated above hot stand by should work also if your routers support it.

IF you find a router which supports RIP or RIP2 then you can re-introduce RIP into eigrp maybe set it up that way.

 

[Matteo Guglielmi]

I did it with GLBP and it works.

The ASUS router now has a single static route to a highly available IP which "floats" (according to some rules) between the 3 cisco routers on the LAN network.

At the end the solution was pretty easy using IOS.

Thank you guys.