Can some point me to documentation on how to setup/configure "Open Data" on ArcGIS Enterprise/Portal (On Premise)?
ArcGIS Online and the ArcGIS Hub is the best platform to share open data. If you're interested in learning more about how to get started I gave a talk on this topic last year - ArcGIS Online: Getting Started with Open Data and Initiatives in the ArcGIS Hub - YouTube and will be giving an updated version at this year's UC on Thursday at 1pm.
In 10.6.1 of ArcGIS Enterprise (due out very soon), we are releasing ArcGIS Enterprise Sites focused at sharing your internal GIS data with non-GIS stakeholders. To learn more, consult the What's New documentation on release. There will also be training seminars in coming months.
While you will have a website data sharing option in 10.6.1, I recommend the Online/Hub for doing Open Data--there are more open data friendly features in Hub than there are in ArcGIS Enterprise Sites.
Happy to answer additional questions!
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