Link to home
Start Free TrialLog in
Avatar of Mcgurupro2
Mcgurupro2Flag for Angola

asked on

What can i look for on Upstream Info when my prefix is not been advertised

I am not too familiar with BGP, but here it goes:

Upstream provider is not been able to advertise my prefix correctly, i guess the guy also don't know what is going on, attached is a sample of Upstream provider's router config including my AS-37011.

I would like to help him out so it can advertise my prefix and fix my problem as well.
Avatar of Pugglewuggle
Pugglewuggle
Flag of United States of America image

Lol why'd you give out your AS number?
Also, no config is attached.
Avatar of Mcgurupro2

ASKER

ooops, config attached this time:

Cheers
Upstream-Provider-Router-Config.txt
No prob!
So your public IP is 66.110.119.238?
BTW where in Africa are you? Just curious.
Cheers back!
I see no problem with that config. Is something upstream of him?
Yes you are correct that is my Public IP and the network needed to be advertised is 41.222.236.0/22, so i am not sure if they are doing it right or not.

Angola - is where i leave.
They've got the neighbor command right, but they are missing the network and aggregate commands.
Neighbor tells who to advertise to, network tells what to advertise, and aggregate address tells how to advertise.
You might provide them with this info - if they have any idea what they're doing they'll fix it quick.
I was just curious when I saw the ASN was in Africa. :)
Will it be possible for you the help me out and write a simple how would the config look like so i can post it to them.

I guess if i tell them only the explanation above it will not be sufficient.
Will it be possible for you the help me out and write a simple how would the config look like so i can post it to them.

I guess if i tell them only the explanation above it will not be sufficient.
Lol no prob. I'm not 100% familiar with BGP but I'll try to help
Here is a good reference on configuring BGP:
http://www.cisco.com/en/US/docs/ios/12_2/ip/configuration/guide/1cfbgp.html
 Try adding:
router bgp 11259
network 41.222.236.0 mask 255.255.252.0
Tell me if that works... if not I'll see what I can come up with!
okie, will go to their site now and check it out, will keep you posted, thanks so far.
kk! No prob!
This is their answer:

1 - The network command
R: I cant network your prefixes. The BGP says that for all the networks that are advertised using the network command the origin of  the ASN will be of that network, What I mean is that Angola Telecom cannot network prefixes that does not belong to our ASN(11259), ohterways your prefix 41.222.236.0 will have the oring 11259 and I am sure this is not desireable.
 
 
2. Aggragate
 
Please refer to the attached diagram:
 
 
 
Router C (AS-300- Simulating Angola Telecom) aggregates the routes 160.20.0.0/16 and 160.10.0.0/16 that come from AS-100(Simulating Mundo startel)( and AS-200-Simulating Another AS we provide transit), respectively. This action occurs because you have configured the aggragate address argument on Router C. Router C only announces the aggregate 160.0.0.0/8 to Router D(Simulating our UPSTREAM e.g:Malasya telecom). The aggregate 160.0.0.0/8 is the classless interdomain routing (CIDR) route. The more specific 160.10.0.0/16 and 160.20.0.0/16 routes are suppressed.  The aggregate route 160.0.0.0/8 is considered to have originated from AS-300 with origin code IGP. The route has lost all the specific AS_PATH information of the individual prefixes 160.10.0.0/16, of AS-200, and 160.20.0.0/16, of AS-100, this is the first reason I cannot use Aggragate.   The specific AS-PATH informnation will be lost.
 
The second reason that I cannot use aggragate is that you have a /22 prefix. We filter based on /24 prefixes. Why should I aggragate this to a more specific route?
 
 
To over come this situation Angola Telecom is going to simulate an ethernet connection BGP session this afternnon. We believe the problem you are facing is to achieve the desireable load sharing/load balancing. We will come back to you ASAP to let you know the test results we have conducted in our LAB enviroments simulating your connection
Example.jpg
Yes, they are right about the network command... why don't they seem to know anything else!? Isn't it their job to know what's going on?
As for the aggregate I'm just not sure... as I said, I'm not a BGP expert although I'd like to get a CCIE sooner or later.
I'm sorry but my knowledge in this area just isn't sufficient to answer your question.
Just being honest.
Cheers! :)
ASKER CERTIFIED SOLUTION
Avatar of Mcgurupro2
Mcgurupro2
Flag of Angola image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial