Hello
We have our AS and prefix two /21.

also we are connected to two peers and both are announcing full bgp table.

Can someone help how we can make load balancing with two peers?

I tried to announce one prefix to one peer and an other prefix to different company with routing filter, i am receving full bgp table from both companies but it doesnot works.

Also i try withh pripend but its not works also, traffic goes with one peer and is comming with different.

Can someone give hint how to do this?
Thank you

Welcome to BGP, a weird and mysterious world where it's normal to have asynchronous routes between any two points on the 'net.

There is nothing you can do with BGP to control your outbound traffic (except maybe to place filters on the advertisements you accept).

For your inbound traffic, prepending only gives you the ability to state a preference. The BGP router at the far end will ultimately make the best decision based on the available information. If you prepend your announcements to Peer1, then the far-end will see that and prefer Peer2. If, however, the far end sees "YOU YOU PEER1" and "YOU PEER2 PEER3" as possible choices, it very well may choose to go through your least-prefered path. That's OK.

If you're announcing 2 /21 routes, you will not have the flexibility to achieve anything close to balance. You can only flip-flop your traffic.

Talk to your providers, get them to allow you to announce /24 routes. This way, you can prepend up to 16 routes total, even putting additional padding on some or no padding on others.

This would also allow you to pad your announcements for blocks used by residential services (assuming that you're saturation is happening during peak residential times), while leaving the blocks used for business customers alone.

Good luck man!