I am new in this kinds of big deployment. OK, I have 2 Internet Service Provider (ISP), ISP-A and ISP-B and also have 2 DC sites and DR sites with same ISP's. I have also own register ASN with /23 block IP's. Following is my diagram.
I have a site www.abcd.com in my web server what are sync with DR web server. So, I want my visitor can access my web site using one single ip resolution against the my FQDN. no required any dns refresh or any dns job.
If you would like to direct the inbound traffic to the server via a single primary path? it would come down to what the ISP will let you advertise to it in terms of subnets.. I did something like it before because the ISP allowed me to advertise a smaller subnet like a /26 from one of the locations.. As well as the overall summary route.. In your case it is /23
So in that case the inbound traffic could come into the site B rather than site A where you may have an overlapped subnet ??
Thank you for your reply. In my case, i have /23 but there the problem is i am unable to route same network to my isp's two different network. I have share the following example.
I have 10.10.5.0/23 and my isp have two different network for DC (188.8.131.52) and DR(184.108.40.206) now my isp cannot ebgp with my same network with their different network. So, i have break my network with 2 different /24 network. and then advertise 10.10.5.0/24 with my DC (220.127.116.11) site and 10.10.6.0/24 with my DR (18.104.22.168). So, in that case how i can unique my IP for my single site without help of dns failover?
Thank you very much for your solution. But i am really new in this job. Can you give me a better understanding to use my diagram. Because in your shared document they use only one router in the top of the diagram and also use same subnet for their second hop router. So, it is confusing for me.