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ASA BGP advertise (not connected) IP Block

I have an ASA connected to a provider. We have our own IP space to advertise. But since it is not directly connected, it will be used for NAT, it is not in the routing table and therefore not being advertised.

I thought once a NAT is configured, that would be the trick, but no go.

How do i get the ASA to advertise the block, when the ASA itself is the destination for that block, and has no route for it?

thanks for any assistance


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VIP Advocate

Is this a public IP address

Is this a public IP address space or a private IP address space assigned to you?

If it is a public address space, request the ISP to route the subnet toward your ASA, then all that is require for proxy ARP to work is to configure NAT on the ASA. 

If this is a private address space going over the providers MPLS VPN network then you will need to advertise the subnet into BGP from the ASA

for example:

router bgp 10

  address-family ipv4



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Re: Is this a public IP address

I know this is an old thread, but I'm looking for any other way to solve this. If my ISP refuses to put in a static route pointing to my public interface, how I can force this route to be advertised in BGP even if it isn't configured locally on the interface?


I have entered a static route for my public subnet and pointed it to the Null0 interface on my ASA. This allows me to have the route installed in the routing table. The ASA states that it is advertising the route to my ISP via BGP, but my ISP is saying they don't see it.