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New Member

Fault tolerance with dual interfaces on one router ????


My situation at a company:

I have two 3548 switches with servers configured with a fault tolerance setup. That means two nics in each server, one connected to one switch and the other to the other switch.

I have a 3640 router with four fast ethernet ports. One is goin to the firewall and the other to a dialin router. So i have two interfaces left for connecting the router to the switches.

I though i could use HSPR, but that it is impossible to configure, that because it will not permit two interfaces configured with an address on the same subnet. Damn, but logical.

My question is:

Is there any way to use these two fast ethernet interfaces for some kind of fault tolerance set or load balancing in combination with the two switches?

Thanx for helping me out


New Member

Re: Fault tolerance with dual interfaces on one router ????

Have you considered utilizing the backup interface command. this will alloy you to apply duplicate IP addresses to multiple interfaces. I suggest setting the backup delay time to 1 and 1. This will get you past the duplicate IP address. Now to get past the arp timeout issue. Either adjust the timeout on the servers or use the mac address command on the backup interface matching it to the primary. The only lose in connectivity will be as the interface changes from standby to active. Hope this helps.

New Member

Re: Fault tolerance with dual interfaces on one router ????

Thanx buddy but there's more

I've tried it and when i'm reloading the router both interfaces come up and there no ip adres working. Probably the IP adres conflict.

How can I solve this problem. I've tried delay time 1 1 already.


New Member

Re: Fault tolerance with dual interfaces on one router ????

Discard the other reply.

I've solved it already. An IOS update did all the wonder.