hsrp

[carl_townshend]

if im setting up hsrp on my 2 internet routers, Do both of the serial cables need to be connected to the isp ?

[ankurbhasin]

Hi Carl,

Not sure if HSRP can be configured even on serial interfaces but yes serial interface can be tracked when hsrp is configured on ethernet interfaces.

Are you configuring HSRP on serial interface? I am not sure how the virtual mac address will be coming in picture in case of serial interface who does not have mac address even.

May be if any one have configured and tried may throw some light on this.

Regards,

Ankur

[atif.awan]

HSRP is meant to provide default-gateway redundancy and is therefore only configured on LAN interfaces (Ethernet, Token Ring). Ankur is correct in pointing out that you can track the state of a Serial interface via HSRP and alter your active/standby states.

On Serial interfaces you rely on routing to cater for device or link failures.

[carl_townshend]

but wouldnt I be actually using it for my lan, both of these routers will be on my lan but the serials connected to the internet !!

[atif.awan]

I was actually answering Ankur's question on the possibility to have HSRP on the serial interfaces.

In your case, yes you will use it on your LAN and you will have to configure it on the LAN interfaces (ethernet probably) of both your routers. One of the routers will assume the role of the Active router while the other will be in a Standby role waiting to take over in case the Active router fails. You need Layer-2 communication between the two routers for them to be able to exchange HSRP messages.

You can configure your active router's HSRP instance to track the serial interface and decrease the HSRP priority to a value less than that of the standby router in case the serial link fails. This way the Standby router will take over the routing for your LAN clients.

You can play with HSRP in a multitude of ways if you want to load share between the two routers but I am not going to go into details of that as I am sure a lot of other posts are available on the same subject.

[ankurbhasin]

Hi Carl,

yes you can configure HSRP on Lan interfaces and track your serial interfaces which points to internet.

Now if you have 2 seial interface each on one router you have to connect both of them with cables to your ISP so that incase one serial interface goes down HSRP configured on lan interface can track that serial interface and make second router as active router and your internet traffic will start flowing to second router and then out from serial interface.

HTH, if yes please rate the post.

Ankur