Re: prefix advertisement in bpg

It doesn't have to be in an IGP (unless you are using IGP sync) but simply the routing table itself, either by a static route or from an IGP.

Regards

David Rothera
CCIE #38338
Sent from my iPhone
Please excuse any mistakes and brevity.

On 15 Apr 2013, at 06:14, Ahmed Hussain <engine10_at_gmail.com> wrote:

> Before BGP can advertise the prefix it has to be in IGP. thats what the
> null route is doing.
>
>
> On Fri, Apr 12, 2013 at 10:01 PM, Imran Ali <immrccie_at_gmail.com> wrote:
>
>> why some bgp implementations adds a null route for advertised prefixes
>>
>> ex
>>
>> router bgp 2
>> bgp log-neighbor-changes
>> network 128.16.16.0 mask 255.255.255.0
>> network 130.130.0.0
>> neighbor 10.10.10.1 remote-as 1 * neighbor 10.10.10.1 advertise-map
>> ADVERTISE non-exist-map NON-EXIST***neighbor 10.10.20.3 remote-as 3
>> !
>> ip route 130.130.0.0 255.255.0.0 *Null0*
>>
>>
>>
>> is has something to do with NAT ?
>>
>>
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Received on Mon Apr 15 2013 - 07:40:17 ART