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rumiclord
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BGP Internal Setup Load Balancing with Failover

Wed Aug 24, 2011 1:13 am

Ok I have setup internal BGP on the 2 routers behind the final border router. For understanding lets say rtr 1, rtr2, & rtr 3. Rtr 1 is doing external BGP with 2 ISP's...Rtr1 is using a static route to Rtr2 for all Public IP's we own, rtr2 & rtr3 are doing BGP for load balancing purposes (I am connecting rtr 2 and rtr 3 via 2 seperate interfaces...using neteq's that only support 20megs atm is the reason for this, so i can neteq 40megs). rtr 3 is doing BGP on the external and OSPF on the inside. Ok now my question is, why did i have to put all of our subnets in the advertisements to make the routing filters work properly. If I put the entire block we own into the advertisements from rtr 3 to rtr 2, the more specific routes and their respective filters are not being used. Using 4.17 on rtr 3 and 5.1 on rtr2, I understand upgrading might be a solution, however these are in production. Has anyone ran into an issue like this before?

Thank you for your help guys.
 
fewi
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Re: BGP Internal Setup Load Balancing with Failover

Fri Aug 26, 2011 7:23 pm

You may have more luck getting an answer if you post some configuration details, including a network diagram, interface statuses, IP addressing and routing tables (unless there's lots and lots of routes), as well as your BGP configuration.
 
rumiclord
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Re: BGP Internal Setup Load Balancing with Failover

Mon Oct 03, 2011 8:07 pm

There are more routes than I would like to post, I was really hoping i could avoid all that since it is not a major problem. I will post a network diagram later today. Fewi I know you atleast know wut I am talking about, does it make any sense to you why I would have to advertise each subnet individually into BGP to make routing filters work. Seems to me I should be able to put 10.0.0.0/8 into my BGP advertisement, and then use routing filters to send 10.0.0.0/16 and 10.1.0.0/16 down 2 different interfaces.
 
miahac
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Re: BGP Internal Setup Load Balancing with Failover

Wed Oct 12, 2011 5:06 am

I am curious to see your network diagram. I am planning (half way through implementing) a similar network. I actually came here to look for a best practices for setting up routes between my bgp edge routers and distribution. What IP's to use? For example

Router1 Peers with L3, they give me a /30 for the wan and a /24 for whatever
Router2 Peers with Verizon, they give me a /30 and 4 separate /24
I am waiting on a direct allocation from arin.

Router 3/4 distribution, They have those 4x /24 and part of the 5th one I mentioned earlier routed out to equipment or customers.
I am using the rest of the fifth /24 to link up the router 1,2,3 (broken into a /30 for each link)
Is that bad? Is there a better way to connect the routers to each other?
 
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mrz
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Re: BGP Internal Setup Load Balancing with Failover

Wed Oct 12, 2011 9:13 am

...does it make any sense to you why I would have to advertise each subnet individually into BGP to make routing filters work. Seems to me I should be able to put 10.0.0.0/8 into my BGP advertisement, and then use routing filters to send 10.0.0.0/16 and 10.1.0.0/16 down 2 different interfaces.
No, you cannot do that. In bgp networks you add specific prefixes that you want to advertise. If you want to advertise 10.0.0.0/16 and 10.1.0.0/16 then you have to add to the networks both of them. Then in routing filters you can accept both prefixes with one rule matching prefix 10.0.0.0/8.
 
rumiclord
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Re: BGP Internal Setup Load Balancing with Failover

Mon Oct 17, 2011 7:14 pm

Thank you Mrz.
 
rumiclord
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Re: BGP Internal Setup Load Balancing with Failover

Mon Oct 17, 2011 7:15 pm

@miahac I will trying to help you a lil later in the day, Working on bandwidth mgmt atm.

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