Eigrp path selection

[kumarpmt83]

Hi,

I have a cisco router 1841 in my client location.

we have connected with two ISP in one router.one is bsnl and other is TATA.

In the router we configured Eigrp protocol.

Config:

int fa0/0

ip address 10.10.20.100 255.255.254.0

Des ###LOCAL LAN####

duplex auto

speed auto

int fa0/1

Des ###TATA WAN###

ip address 10.70.128.63 255.255.255.252

encapuslation PPP

bandwidth 512

int se0/1/0

Des ###BSNL WAN###

ip address 192.168.63.25 255.255.255.252

encapuslation PPP

bandwidth 2048

  router eigrp 20

  no auto-summary

  network 10.10.20.0

  network 10.70.128.0

  network 192.168.63.0

My question:

Our aim is BSNL should be work as primary link.If BSNL link fails means it should take TATA route.

And after BSNL link came means it should be working bsnl link.

How we give the BSNL as primary.

Any other configuration needed for the fall back.

Kindly tell me anyone.

[Marwan ALshawi]

hi

in eigrp you can use bandwidth and delay to change the path selection

you already increased the bandwidth on the BSNL

what you need to do is make the other link with a high delay value and the BSNL with low delay value

hope this help

[kumarpmt83]

What is delay value ??

how to calculate the delay value???

[Vasileios Bouloukos MSc, ITIL, CCIE]

Delay value is applied to the interface of the router in order to affect the path selection.

Please, check the next link

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a00800c2d96.shtml

Hope that helps,

Vasilis

[RUSTOM BILLIMORIA]

Hi Dinesh,

Was hoping to shed some light here. It seems that you are trying to use Eigrp to select best path towards your service provider. If that is not true, my apologies for the misunderstanding. If yes, then It cannot be done via EIGRP. you will require a First hop redundancy protocl such as HSRP. Please do provide details about other devices of your network for me to understand better. If both links are connected to the same router then you would need a static route that is tracked via IP SLA.

Cheers.

Rustom Billimoria

[Vasileios Bouloukos MSc, ITIL, CCIE]

Hi,

I do not find any reason that you can not run EIGRP with the ISP router.

According to Dinesh config the WAN links are configured with EIGRP. If the ISP has not any problem (e.g. the ISP routers should be CISCO to  run EIGRP) the primary-backup setup can be achieved with EIGRP too. The configuration to have primary/backup setup can be achieved as described to my previous post.

If the client router should receive the full internet routing table, then I agree the EIGRP could be a problem and BGP should be used. However, since the client router is a 1841 I do not think that this is our case (Dinesh can confirm that) and it will receive a summary (or default) route by the ISP.

Hope that helps

Vasilis

[RUSTOM BILLIMORIA]

Hi,

Since Dinesh did not specify anything about the SP running EIGRP, I assumed they don't. Maybe after all these years of tshoot, I always tend to assume the worst. . Dinesh pleaes do confirm that the sp is running eigrp and what kind of routes you are receiving from both. As I did mention in my earlier, apologies for the misunderstanding.

Sent from my BlackBerry® smartphone from Tata Indicom

[kumarpmt83]

In the Service provider end they do only static routes.

[RUSTOM BILLIMORIA]

Hi Dinesh,

So do you confirm that there is no eigrp running between you and the sp or

that there is eigrp but they only provide static routes via eigrp ?

Just trying to clear out what you said.

Regards

Rustom Billimoria

CCIE R&S# 24798

Sent from my BlackBerry® smartphone from Tata Indicom

[Vivek Ganapathi]

Hello Dinesh,

This is the second time you have been asking the similar question. I believe, this was answered very clearly to you with a diagram. I am unable to find the thread, but yes this was answered in detail.

Just to help us all, Please DO NOT Mark a thread as "Correct Answer" if you still have confusion or have some clarifications, you should continue on the same thread.