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BGP - controlling default route advertisement

I have a router at a datacenter, we will call MAIN-ROUTER, which is advertising default routes over BGP to a remote site; we will call it REMOTE-ROUTER. Directly connected to the MAIN-ROUTER is an ASA firewall called MAIN-FIREWALL. This firewall is connected to the Internet and is the gateway for the entire network. The router needs to advertised the loopback address of the MAIN-FIREWALL to the REMOTE-ROUTER, but it doesn't. It advertises itself. Here's more details:

MAIN-ROUTER IP is 192.168.101.3

It is directly connected to MAIN-FIREWALL, which is 192.168.101.1

MAIN-FIREWALL has a loopback of 1.1.1.1 that all routers hit in order to reach the Internet

REMOTE-ROUTER IP is 172.24.33.1

MAIN-ROUTER has these static routes:

ip route 0.0.0.0 0.0.0.0 1.1.1.1

ip route 1.1.1.1 255.255.255.255 192.168.101.1

(so 1.1.1.1 is it's default route, and it knows how to get there)

What I want is MAIN-ROUTER to advertise the 1.1.1.1 route exactly as it appears in its own routing table. It should appear like this in REMOTE-ROUTER's table:

B*     0.0.0.0/0   [200/0]  via  1.1.1.1,  00:27:58

But instead it appears like this:

B*     0.0.0.0/0   [200/0]  via  192.168.101.3,  00:27:58

MAIN-ROUTER is electing itself as the default route, and that's bad because all traffic bound for the Internet is passing through MAIN-FIREWALL twice.

The idea behind all this is that there is a second datacenter that is also advertising the default route but with a lower weight, so when the main site goes down, all the remote routers grab the backup site's route and continue operating. It all works just fine, but the load on the firewalls is twice what it should be.

MAIN-ROUTER BGP CONFIG:

router bgp 100

no synchronization

bgp log-neighbor-changes

bgp update-delay 10

network 0.0.0.0

timers bgp 10 20

neighbor 172.24.33.1 remote-as 100

neighbor 172.24.33.1 next-hop-self

no auto-summary

REMOTE-ROUTER BGP CONFIG:

router bgp 100

no synchronization

bgp log-neighbor-changes

bgp update-delay 10

timers bgp 10 20

neighbor 192.168.101.3 remote-as 100

neighbor 192.168.101.3 next-hop-self

neighbor 192.168.101.3 weight 40000

neighbor 172.24.200.1 remote-as 100

neighbor 172.24.200.1 next-hop-self

neighbor 172.24.200.1 weight 30000

maximum-paths 2

no auto-summary

(172.24.200.1 is the backup site)

I need one of three things:

A way to force BGP to advertise the default route exactly as it appears in the routing table.

A way to force BGP to advertise an arbitrary route of my choice.

If all this is impossible, I need a better solution for failover.

I really appreciate any feed back, thanks!

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BGP - controlling default route advertisement

Duplicate post, please use the link below to post any responses -

https://supportforums.cisco.com/thread/2264473?tstart=0

Jon

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