Does anyone know if you can monitor websites with the http or https template to servers that are not in the Orion DB ?
Yes, you can absolutely do that. APM needs you to assign it to a node for internal reasons, but it doesn't matter which node. E.g., you could poll www.solarwinds.com with the HTTP monitor without adding any of our web servers to your Orion, but you would need to nominally assign that monitor to some node in your database.
