Configure cisco 2651 router to failover to second T1

[mdwu]

Hi All,

I have two questions. My cisco 2651 router has 2 WAN T1 DSU/CSU internal card and 2 Fast Eth connection. So now I have 2 T1 access.

First question: How do I configure so that when my primary T1, for example fa0/0 fails, it will automatically failover to use my second T1, fa0/1 for internet access.

Second question: We have branch office in london. I want to configure a permanently VPN connection from NY to london.

NY router cisco 2651
London router cisco 806

Please provide sample config. Thanks.

 

[cyberkatis]

The easiest way would be to implement HSRP....

Hot Standby Routing Protocol can be easliy looked up on Cisco's website.

Hope this points you in the right direction.

Chris.

 

[mdwu]

thanks, but I only have one router. HSRP is this for two seperate router

 

[BuckWeet]

well you can do this two ways

one would be via static routes, put a lower metric on your primary one, then when that link goes down it'll kick over to the 2nd...


or you could do a backup interface, so when the primary fails, it'll turn up the 2ndary..


BuckWeet

 

[routerman]

You may run into problems with the backup/failover. The router can only make the switch over if its directly connected interface goes down, which may not happen if the line on the other side of the dsu fails.

You need to test this, otherwise you could end up in a situation where you expect it to fail over when the line fails, but it dosent.

May be worth talking to your ISP about this as well.

As for your VPN, what IOS versions are you running?

 

[mdwu]

To: Routerman, IOS 12.2

Thanks for all reply, However, I am more of a system admin guy than network guy. if anyone reply with sample config, that will be much appreiciated.

thanks again

 

[StretchedTech]

I have a similar question. I'm using a 2620 with two different ISP's. My main provider is on inferface S0/0 my second provider will be on Fa0/0. It will be with 2 different ISP's. If you need any more info please let me know.

 

[mdwu]

Hi Stretchtech,

I am a bit confuse with your setup..if it's two T1 coming in, then you should have two serial connection for ISP, then the Fa0/0 and/or fa0/1 for internal network.

 

[StretchedTech]

My mistake you are correct two serials S0/0 (Primary ISP) S0/1 (Secondary ISP).

 

[routerman]

Stretchtech,

With 2 serial interfaces you can use the either the floating static route method or use the backup statements as described by Buckweet earlier in this thread. These both rely on the interface state changing to down to start the backup process.

Have you thought about incoming traffic, have you discussed with both ISP's how your network is advertised when one link fails?

 

[mdwu]

Stretchtech....seems like ppl gave up gave up answering this.

Anyway, since both my failover and primary T1 are from the same ISP, their tech guy told me that I don't know to do anything on my router, they can configure that on their end since they control the Ip block that's given to me..

So, check with your ISP,

 

[rcasta]

mdwu,

For having this 2nd T1, are you charged on a monthly basis? or only in case it may be used as a backup link? Because I would load balance traffic between them with static routes and end of the story.

cheers,

 

[mdwu]

rcasta,

Yes, For the backup, we do have cap limit per month, therefore we cannot load balance. If in case the Pri T1 fails, since it's the same ISP, they will not charge us of using it, even if it goes over cap limit.