One of my client has the following setup.
They have a webserver say abc.com with a public ip say 220.127.116.11 at their HQ.
The client owns the primary dns server for abc.com and is located at HQ and secondary DNS for abc.com is the ISP DNS Server.
Whenever there is change in the DNS entries for abc.com, they modify their DNS server which updates the ISP DNS server which in turn propagates the changes to internet.
This setup is working perfectly fine without any issues.
Now, the client is setting up a DRC (disaster recovery center) located few kms from HQ and connectedd via MPLS. The DRC has its own leased line internet connectivity from the same ISP.
The public ip address of the abc.com server at DRC is say 18.104.22.168
Now the Client has bought a GSS-4492R (rather sold by our PSE & Cisco SE). As per design from CISCO SE, its to be installed at HQ and it will redirect the traffic for abc.com to 22.214.171.124 incase 126.96.36.199 at HQ becomes unavailable due to any reason (provided only 188.8.131.52 server is down and other network infrastructure is running)
I am wondering how GSS will perform the above functionality without disturbing the existing DNS setup. The client doesnt want to disturb their DNS Setup.
Please advise me about the role this GSS can play & add value in the above scenario.