Hi all, I'm looking for a bit of help regarding migrating to Enterprise. Our organization is updating to ArcGIS Enterprise from a standalone 10.4.1 server. We are adding another machine to help with arcgis server load and installing the base deployment on it. Our current 10.4.1 ArcGIS Server machine also acts as a webserver. I was thinking option 3 would be the best option below as I plan to federate this machine to the new base deployment in order to not have to republish services. Right now the 10.4.1 server has webadaptor, arcgis server and hosts our website. Would there be any issue federating this server to the base deployment? Or should I upgrade in place and use the new server as an added hosting server. Since the 10.4.1 machine has our ssl cert, external website and webadaptor, perhaps Enterprise base would be best installed on this machine?
"The result of Option 3 is a base ArcGIS Enterprise deployment with an additional ArcGIS GIS Server site. Option 3 uses new infrastructure for the base deployment and upgrades your existing ArcGIS Server site to a federated GIS Server site within the ArcGIS Enterprise deployment. As in Option 1, the key benefit of Option 3 is that it does not require that existing services be republished, and service URLs are not changed. However, because you are adding new, separate, infrastructure for the base deployment you will need to purchase additional cores of ArcGIS Server."
It sounds like there'd be less moving parts if you incorporated that existing Server into your Enterprise as either a federated Server or the hosting Server. If there are enough resources on the machine, everything can exist on that one box, otherwise you'll need to look into a distributed environment where Portal and Data Store are on separate machines.
To answer your question, no there shouldn't be a problem federating your existing Server with Portal. Take care to understand how security for existing services will be affected, though, This is described in the Federation section:
There is a tie-in between federation as defined by the IT industry and as used within ArcGIS Enterprise. The tie-in is that once you federate your ArcGIS Server site to an ArcGIS Enterprise portal, the ArcGIS Enterprise identity based security model will take over, meaning any security you had previously set on your ArcGIS Server site will be bypassed by the identity-based security you set within the portal.
Once you have federated an ArcGIS Server site to Portal for ArcGIS, security is handled by the portal; only users who have an identity in your portal will be able to view secured content. Therefore, when you migrate a standalone ArcGIS Server site to ArcGIS Enterprise you will need to recreate your security structure using the ArcGIS Enterprise security model and give everyone who requires access an identity within the portal.
Thanks Jonathan, my only other question is in order to keep from republishing my services, does it matter if I incorporate the existing server as hosting or federated?
No, it doesn't matter. You can configure a new server for the hosting server or just reuse your existing server as the hosting server. The latter is an easier option for your users/applications as the URL to existing services likely won't change, unless you decide to change the front-end to the Server, (change the machine hosting the web adaptor or reverse proxy, for example).