I've installed ArcGIS Server 10.6 on a Windows Server 2016 DataCenter Azure VM and bound it to an SSL certificate which was generated using our internal Microsoft CA. This has worked out fine as far as I can tell.
On a separate Windows Server 2016 DataCenter Azure VM, I installed a Web Adaptor and after attempting to add the ArcGIS Server above to the configuration, I received the following error:
If I install the Web Adaptor on the same VM as ArcGIS Server then it all works out fine. However, the goal is to have a separate VM for the Web Adaptor.
Can you please advise where I may be going wrong?