Hi,

We have a web based client-server product. The client is expected to be used in the upwards of 1M users (a famous company is going to use it).

Our server is set up in the cloud. One of the major questions while designing is how to make the whole program future proof. Say:

1. Cloud provider goes down, then move automatically to backup in another cloud
2. Move to a different server altogether etc

The options we thought till now are:

1. DNS: Running a DNS name server on the cloud ourselves.
2. Directory server - The directory server also lives on the cloud
3. Have our server returning future movements and future URLs etc to the client - wherein the client is specifically designed to handle those scenarios

Since this should be a usual problem, which is the best solution for the same? Since our company is a very small one, we are looking at the least technically and financially expensive solution (say option 3 etc)?

Could someone provide some pointers for the same?

K