cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
771
Views
0
Helpful
11
Replies

Bgp advertisment to a specific neighbour !!

illusion_rox
Level 1
Level 1

Hi all, suppose i have 10 neighbours configured in bgp process of RA, now i want to advertise network 25.0.0.0/8 to only neighbour 12.0.0.1 in the same AS, i want to do it using the minimal set of commands, how can i do that ?? i dont want to advertise 12.0.0.0 to other neighbours except 12.0.0.1 ok

Thanks

11 Replies 11

bvsnarayana03
Level 5
Level 5

Hi,

Its possible to achieve what you have mentioned.The method is called "conditional advertisements" & is implemented with the use of advertise-maps.

Pls refer link for configuration help:

http://www.ciscopress.com/articles/article.asp?p=169556&seqNum=2

hi narayan, what i actually want is to tell the bgp process to advertise a particular prefix to a particular neighbour only, in case of conditional advertisement can you provide the configuration of my case ??,

Thanks

Hi Ovais,

You need to do prefix filtering using prefix-list or route-map, for simplicity you can use a prefix-list that filters the undesired prefixes while permitting any other prefix.

The prefix-list entry that permits any prefix is:

ip prefix-list FILTER permit 0.0.0.0/0 le 32

Apply the prefix-list to the neighbor:

neighbor x.x.x.x prefix-list FILTER out

BR,

Mohammed Mahmoud.

Hi Mohammad, you mean to say that i want to deny prefix 12.0.0.0/8 to my 9 neighbours so i need to apply prefix-list out to 9 neighbours right ??

Now kindly try to get my point is that i want to define some condition on the network itself to be advertised to a specific neighbour !!

Hi,

Ok, the only thing that comes to my mind right now is using peer group to group the 9 neighbors, but there is a trick here, you can't define a specific outbound routing policy to a single peer-group member, outbound routing policies can only be applied to the whole peer-group.

BR,

Mohammed Mahmoud.

hi Mohammad, i didnt noticed you were a CCIE, well i guess then what you are suggesting is perhaps the only option left, i need to ask something regarding the CCIE lab itself, what i know is that by the end of lab there should be full reachability, but we may be required to perform some filtering in which case a router may not have certain routes in Routing table so how come full reachability can be achieved ??

Hi,

Yes, perhaps :) As for the full reachability in the CCIE lab, this excludes any route that was explicitly required to be filtered on a specific router(s), double checking with the proctor in such case is your best option.

BR,

Mohammed Mahmoud.

Mohammad can you also tell me that how much qos comes from a switching point of view ?, i mean to say how much area is covered by 3550/3560 switches in the lab ??

Thanks this is my last question :)

Hi,

You are very welcomed :) Actually this is a question that i can't answer in details, because of 2 aspects, first this was never declared by Cisco anywhere, secondly according to the NDA i can't inform you with my exam details. But frankly speaking baring in mind the massive points that needs to be covered in the exam, i guess Catalyst QoS if covered won't be a big part.

For more details, the below link is a wonderful link about CCIE Catalyst QoS:

http://classroom.internetworkexpert.com/p95576427

BR,

Mohammed Mahmoud.

Is it covering everything regarding catalyst QoS ??

Hi,

No, but beside the CoD and Cisco DocCD and your lab you'll find your way.

BR,

Mohammed Mahmoud.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: