We have two ISP's and both ISPs' IP NAT with the same webserver IP. I want failover for incoming traffic, is there any open source solution? Can I do it by making two name servers, one for each ISP?
I am not sure but as per my knowledge the primary and secondary name server will reply in a round robin fashion till they are live. Once any name server will be unreachable then only another will be replying, so if I am right then I think I can do incoming failover by making two name servers in my office...