It sound like there may have been an issue upgrading your server. Did you upgrade all the machines in your GeoAnalytics server site? Did you unfederate your GeoAnalytics server before upgrading (you don't need to)? I would recommend calling into Esri Technical Support, they'll be able to do a better job supporting you in this case - where a screen share will be helpful.
Product Engineer, GeoAnalytics Server
Thank you Sarah.
Something funny did happen during the upgrade, and I thought that I was able to unfederate properly.
Since it is just a VM, I'll delete and re-create.
So it looks like the problem was in Portal.. I had to uninstall and reinstall it to get things working. I'm sure there might have been another way especially if there were maps/apps etc... but fortunately I didn't have anything too valuable in there.
I think that the moral of the story would be to unfederate before upgrading from now on.
If you had any logs or information from the original failure that would be very helpful to us. We do not suggest unfederating a server before upgrading, especially if that server is your hosting server. There are item id's shared between portal and server that will be lost once you unfederate.
Thanks for the info Niccole. Unfortunately I don't have any logs - this was for a DEV environment so I really wasn't paying too much attention during the upgrade.
But the one thing that I did do was follow Jonathan's instructions in to clear up the GeoAnalytics server from Portal during the upgrade.
This may be a bug:
BUG-000113688 - Portal for ArcGIS 10.6 fails to set Raster Analytics server and returns the error 'Error while processing request. Internal error. JSON response not set.', if hosting server protocol has been updated to HTTPS
It's logged against 10.6, but it may occur at 10.5.1. It's also logged against Raster Analytics but the details of the bug indicate it happens with GeoAnalytics as well.
If this is indeed specific to HTTPS only, first verify if you've set the Server to be HTTPS only. If so, set it to HTTP and HTTPS, federate, and then set it back to HTTPS only if need be.