Prior to 10.6.1, I was using the ArcGIS Server Admin Toolkit to stop and start services in bulk. That toolkit has depreciated and does not appear to work in 10.6.1. (It could be that I'm making an error with the parameters, but I don't think I am) Then I found this:
Example: Stop or start all services in a folder—ArcGIS Server Administration (Windows) | ArcGIS Ente...
The above script assumes that you are using port 6080, but ours are on 6443. I tried to change the parameter in the same script from 6080 to 6443, but that did not work. Again, I'm not ruling out the possibility that I'm entering the wrong variables, but the error message says that the server is forcibly closing the connection to port 6443 when I run it.
In scouring the forums, I've seen comments that suggest that A) you cannot start/stop services using Python if said services are secured (https), and B) the Esri is intentionally not maintaining or developing tools to allow you to batch start/stop services anymore because they want you to do it through Server Manager/Portal/ArcCatalog. I know you can't start/stop services in Pro yet, but that it might be coming in a future version.
Can anyone help me fill in the gaps? My ultimate need is to be able to stop all web services at once and then restart them in bulk. I'm using Enterprise 10.6.1, including Portal. I published all of my services to Server using ArcMap 10.6.1.