Hi Michael, In this scenario, you would need to set up a split-brain DNS configuration. This allows you to use the same domain name for both your Azure web server and your 3rd party Exchange server, while still maintaining separate Active Directory instances. Here are the general steps to set up a split-brain DNS configuration:
- Create a new subdomain for your Azure web server, such as "web.yourdomain.com".
- Create a new DNS zone in Azure for the "web.yourdomain.com" subdomain.
- Add a DNS record to the "web.yourdomain.com" zone for your Azure web server's IP address.
- Configure your Azure web server to use the "web.yourdomain.com" subdomain for its web traffic.
- Set up a split-brain DNS configuration with your domain provider, so that requests for "yourdomain.com" are resolved to the Azure web server's IP address when coming from the public internet, but are resolved to the 3rd party Exchange server's IP address when coming from within your network. By setting up a split-brain DNS configuration, you can use the same domain name for both your Azure web server and your 3rd party Exchange server, while still maintaining separate Active Directory instances.