BGP

[Nicholas Vigil]

I have an Internet router running eBGP with my ISP. My Internet router is receiving a default route learned from the ISP. My Internet router is is then redistributinging itself as the defualt route to my internal router/network via iBGP. This works fine. My only poblem is that when I lose my Internet connection my Internet router loses its default route as expected, but my internal router will not drop its learned default route to the Intenet router unless I clear the routing table entry. I need the internal router to drop its learned default route if my Internet router loses its default route from the ISP.

Any help would be greatly appreciated.

[jheckart]

If you were to configure a static default route and then redistribute it to iBGP, you wouldn't have this problem. Is that an option for you?

[Nicholas Vigil]

I tried adding a static default route on my Interent router that points to my ISP instead of receiving it via eBGP from the ISP. My internal router which runs iBGP with my Internet router still does not drop its default route when the link to the ISP goes down.

[mheusinger]

Hi,

can you at least provide the BGP configs of your routers and any default route relevant config?

Second, are you using any dynamic IGP like OSPF? Then it would be more simple to use it to announce the default route from your internet router:

router ospf 10

default-information originate

This will only distribute the default route, if the BGP router has it in the routing table.

This will also work with a redundant setup (slightly modified, though).

Regards, Martin