Two ISP links on Single cisco router with Folt tolenrance and load Balance

Unanswered Question
May 11th, 2008

Dear All,

How are you doing?

Anybody i have one cisco and another is non cisco router each router have a one ISP Link , now we have to remove non cisco router and terminate the link which was on non cisco . on cisco router. Could you tell me how to configure load balancing as well as fault tolerance on Cisco router or Do you have sample configuration on this?

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (1 ratings)
spremkumar Mon, 05/12/2008 - 00:58


Can you revert back with the routing policies being followed at present for forwarding the packets to the isp ?

Also are you currently running any routing protocol with ur isp.


atul.trivedi12 Mon, 05/12/2008 - 01:13

thax for support , presently i did nt see config of tht routers , i have to visit on tht site , so i just wanted to knw the basic things which i have 2 remember before doing any changes , if be possible then can u please give me a basic idea .

Richard Burts Mon, 05/12/2008 - 02:44


If you could provide more information about how it has been set up we might be able to give better advice. But in general the basics are:

- it is easiest and most simple to configure 2 static default routes, one to each ISP. This will provide for load sharing and provide redundancy. If one ISP link fails then the other link will carry all the load.

- for the failover to work effectively your router must be able to detect if the link to an ISP goes down. For point to point serial links this is easy. But if the link to the ISP is Ethernet then it is possible that the ISP may have problems and not be responding to you but the interface will still be up and you will still attempt to forward traffic to that ISP. To deal with this you may want to do Reliable Static Routing Backup Using Object Tracking. This link will give information to help get you started with it:



atul.trivedi12 Tue, 05/13/2008 - 00:14

thax a lot,I am attaching a sample network diagram , i want to shift both ISP link on cisco router , and wanna use realtime router as a backup router , at tht condition when our cisco router goes down then with minimum business impact can i use my realtime router as a backup router , when realtime router having only one serial interface and one fast ethernet . so could u please suggest me.



This Discussion