If you run an IGP it will be easier since the routing protocol will decide automatically which path to use (MPLS or VPN) and you decide that MPLS has priority).

If you use STATIC routes, you can as well configure this redundancy.

A GRE tunnel is a way to encapsulate any kind of traffic in unicast GRE packets, so that they can travel inside an IPsec tunnel or any other media.

GRE allows to run an IGP through it and still be protected by IPsec.

Federico.

An example of floating static routes:

ip route 0.0.0.0 0.0.0.0 MPLS 1
ip route 0.0.0.0 0.0.0.0 VPN 100

In this way, the route through MPLS will be preferred over VPN.
The problem with static routes is that they won't change unless the next-hop fails, so to overcome this problem you should track
the route.

Here you can use the IP SLA feature to track both routes and in this way, when the MPLS route goes down, the VPN tunnel will
establish and if the MPLS comes back, it will again become the primary connection.

Federico.

Thanks Federico. Could I use a floating static in combination with the IBGP routes learned from the MPLS? So that I could have for instance 10.0.0.0/24 learned from BGP with admin distance 20, and 10.0.0.0/24 static with admin distance 100. And then somehow make the static have lower admin distance when the IP SLA fails?

Thanks again for your help.

dmurray14 wrote:
Thanks Federico. Could I use a floating static in combination with the IBGP routes learned from the MPLS? So that I could have for instance 10.0.0.0/24 learned from BGP with admin distance 20, and 10.0.0.0/24 static with admin distance 100. And then somehow make the static have lower admin distance when the IP SLA fails?
Thanks again for your help.

Dan

Just a quick question. Are you doing this all on the same router ie. does the VPN and the BGP connection go from the same router ?

Jon

Hi Jon,

Yes, as of now the plan is to run this on the same 2800 on both ends. Is this not OK?

dmurray14 wrote:
Hi Jon,
Yes, as of now the plan is to run this on the same 2800 on both ends. Is this not OK?

No that actually makes it easier. As federico says you don't need to use IP SLA because if you have 2 routes on the 2800 ie.

10.1.1.0/24 learnt from BGP - is it EBGP or IBGP ?  either way this route is only learnt as long as the MPLS connection is up

10.1.1.0/24 added as a static route ie. ip route 10.1.1.0 255.255.255.0 250 <-- make this AD higher than 200 if IBGP. This route will not be inserted into the routing table unless the EBGP/IBGP route is lost.

then if the MPLS connection fails you lose the EBGP/IBGP route and the static route would be used. If the MPLS connection comes back up you learn the route again and as it has a lower AD than your static route it is now used. So because you are using a dynamic routing protocol you dont need to worry about IP SLA.

Jon

Great thanks, Jon. My only concern is, what would the reaction time be on this? Assuming the local loop went down, or anything else in between, how long would it take for that route to clear? Would and IP SLA speed up the reaction time?

Thanks again!

Use floating static, set static router with different administrative distance.

Exactly.

You can use the floating static routes in conjunction with the iBGP-learned routes.

By setting the administrative distance (lower or higher), you tell the router to either prefer or not the static routes over  the iBGP routes.

Federico.

Great, thank you. What is the best way to insert the static route when the IP SLA fails? Do I have to use the tricky boolean solution described here:

http://blog.ioshints.info/2007/08/install-static-route-when-ip-address-is.html

Or is there a better way?

Thanks again!