Standby

[ntran]

I have task before me that I am not sure how to handle this. I would appreciate any suggestions you all can give.

We have 2 Cisco Routers 2621(each has 1 DSU T1 & 2 Fas Ethernet). We have 2 Internet Service Providers (ISP#1: T1 and DSL. ISP#2: fractional T1). Between 2 Routers, we're using Cisco Fas Hub 420 as HSRP Virtual Gateway and this hub connected to our internet network protected by Watchguard Fixbox1000

Current the setup like this:
R1 is active using T1(Serial) from ISP#1. Fas0/0 to C420 to Fixbox 1000

Would like to do:
R1 If T1 is going down, DSL from ISP# will kick in (Fas0/1)
R2 If both T1 and DSL are down the T1 kick in.

Could this done? Thanks.

 

[carlosAlberto]

ntran,

I have done some HSRP testing before. As far as i'm aware i don't think this can be done.

The problem is: HSRP looks at priority values on the router not the link.

The cisco site is very helpful, try getting in touch with someone there.

 

[jgercken]

HSRP CAN do this using a feature called HSRP tracking. Basically it modifies its priority based on if a link is up or not. The trick is that it can only use its own interfaces (up or down). It will decrease it's priority by the amount specified.
standby 1(group#) track s1/0 10(default value)

Hope this helps. If it does - rate my post.
Jeff

 

[jgercken]

Ok, to improve my answer. -yes I'm bored.

On R1 set a static route 0.0.0.0 0.0.0.0 out serial
then set another static route pointing out Fa0/1 but with a metric higher than for the previous one. (called a floating static route)
Unfortunately the R1 will never know if the DSL line goes down unless you can get your isp/DSL modem to send routing updates. (or buy a Cisco ADSL card for R1)


Do the HSRP stuff to switch to the other T1 if R1 fails.

I have to admit I don't understand why you've got 2 routers but then pipe the traffic to 1 hub and 1 firewall. Seems like a false sense of redundency because you still have a single point of failure.

Also this will only work for traffic/connections initiated from internal sources, ie web browsing, checking mail, etc. Nobody from the outside will be able to get to any internal machine, ie web server, mail server, etc. The real solution is to get a BGP AS number and exchange routing updates with both your ISPs. That way you could actually load balance out all of them. (ok maybe not the DSL -depends)