Good Morning, (here at least)
We are pretty new to BGP. We have two upstream providers, I'll just call them ISP1 and ISP2. We are receiving the full routing tables from both upstreams. We have 4 /22's and 1 /24 from ARIN. We are advertising these prefixes to both upstreams. While turning up ISP2, literally after doing so we had a fiber cut on ISP1. Everything worked great and BGP did it's job.
The goal is to be able to say prefix 1, 2 and 3 go out ISP1 and prefix 4 and 5 go out ISP2. When we do this we appear to be breaking DNS and I it's because the way the traffic is going out and coming back in.
So right now I am testing our /24 because it has 2 customer's behind it so far.
Here is how our filters are currently setup: (not using our actual IP's here, just examples)
add chain=ISP1-out prefix=10.0.0.0/22 action=accept
add chain=ISP1-out prefix=10.100.0.0/22 action=accept
add chain=ISP1-out prefix=10.200.0.0/22 action=accept
add chain=ISP1-out prefix=10.300.0.0/22 action=accept
add chain=ISP1-out prefix=10.400.00/24 action=accept set-bgp-communities=6461:5060 set-bgp-prepend=3
add chain=ISP2-out prefix=10.0.0.0/22 action=accept set-bgp-prepend=3
add chain=ISP2-out prefix=10.100.0.0/22 action=accept set-bgp-prepend=3
add chain=ISP2-out prefix=10.200.0.0/22 action=accept set-bgp-prepend=3
add chain=ISP2-out prefix=10.300.0.0/22 action=accept set-bgp-prepend=3
add chain=ISP2-out prefix=10.400.00/24 action=accept
So on the /24, I am wanting that to go out ISP2 and back into ISP2. Coming in from the outside, that works. However, traffic from our router still wants to go out ISP1 for the /24. So I believe that is where my problem is coming into play. What am I missing here to make traffic from our router from the /24 to go out ISP2 and not ISP1?