Port redundancy in Router

[gladwin17]

I have a single router with 2 ethernet ports,both are connected two seprate switches both are in same network.Usually both switches r connecting to the router through ethernet port 1,ie switch2 will connects to sw1 and that to eth1.when the eth 1 fails I want sw 1 to connect to sw2 and eth2 should come up with the same ip.how will I configure this for port redindancy?Can I use HSRP for this?

[ankbhasi]

Hi Gladwin,

You cannot configure HSRP on same router and you need to have minimum 2 routers for the same.

But I believe what you can do as a workaround is configure port channel on your router and assign an ip address to the port channel and you can assign the 2 physical ports on your router eth1 & 2 to that port channel.

On the switch also you can have a layer 2 etherchannel and cofigure the 2 ports in same etherchannel bundle.

HTH

Ankur

[gladwin17]

Hi Ankur

Thank you for your reply.

Will that port channel configuration work for a layer2 link?If so will it give me redendency between the ports?Or is it only for load balancing?

Regards

Gladwin

[gladwin17]

Will it work for a l3 link?

[ankbhasi]

Hi Gladwin,

Yes port channel is for layer 3 which you will configure on router and etherchannel is for layer 2 which you will configure on layer 2 switch connected to router.

This will also give you redundancy as well as load balacing.

So if one port of router or switch goes down traffic will still keep passing.

HTH

Ankur

*Pls rate all helpfull post

[arunec539]

Hi Ank,

The topology I have is the same. Router R1 , Port 1 goes to switch 1, port 2 goes to switch 2.

I am configuring port channel on the router and Ether channel on swtich2.

should there be a link between switch 1 and 2 and stp enabled.

[mahmoodmkl]

Hi

hope this link will help u.

http://www.cisco.com/en/US/tech/tk389/tk213/technologies_configuration_example09186a0080094958.shtml

Thanks

Mahmood

[paul driver]

Hello

Most simplistic method would be apply backup interface on the rtr if supported:

example:
rtr 
int x/1 primary
int x/2 secondary

int x/1
description Primary interface
backup delay 30 30
backup interface x/2

[arunec539]

Thanks for your reply.Just wondering if there is a way redundancy can be achieved at the acces layer 

I have two switches as said earlier. One of my switch rebooted last time and we have brought a new switch. Wondering how could I connect the switch to port 3 of the same router and push traffic to it.

[arunec539]

Hello Paul,

What I heard is to set the same ip address on both the interfaces . Is that true or should I not be setting the ip address on the back up interface. Thank you!.

[arunec539]

Thank you very much sir .It worked!!!

Also, I have an issue with the tacacs, where it says accounting created for this user and doesn't go beyond. Wondering if there is an issue with the cisco c1111 router.

[paul driver]

Hello
If you another query please create another post so it can be dealt with separately, don’t forget to mark this post as solved if you’re are happy with the solution provided .