My goal: To overwrite a Map Image Service in Portal/ArcGIS Server ArcGIS Pro 2.9.1, so that URLs to the service remain unbroken.
I am no stranger to ArcGIS, but Portal is new to me at this new job. I have modified the symbology of a layer in an ArcGIS Pro project that was originally used to publish a map image service in Enterprise. I am logged in to Pro using the same user name that owns the item in Portal. When I go to the Share ribbon > Share As section > Web Layer drop-down > Overwrite Web Layer, I cannot see the map image service I want to overwrite. When I click the type drop-down box, it only contains "Web Feature Layers" as available options, therefore, I cannot select the map image service by name and the tool can only be cancelled.
What else I have tried: 1) I found an old ArcMap document containing the same layers. I modified the symbology of the one layer and went to File > Share As > Service > Overwrite, and was told later in the process that ArcMap cannot be used to overwrite services originally created in Pro. 2) I have attempted several times to create an administrative connection to ArcGIS Server, but always end up with a User connection, even if using .ags connection files that originally had the administrative privilege. 3) I have looked at privileges and I believe everything is in order.
Documents I have read:
https://community.esri.com/t5/arcgis-pro-questions/the-map-image-cannot-be-overwritten-arcgis-pro-2-2/m-p/239840#M10427 (where the screen shot shows other item types besides Web Feature Layers)
https://pro.arcgis.com/en/pro-app/latest/help/projects/connect-to-a-gis-server.htm Where it talks about Federated ArcGIS Server and Portal, which I believe I have
https://pro.arcgis.com/en/pro-app/latest/help/sharing/overview/overwrite-an-image-service.htm Which I'm unable to follow because of my Server connection type.
Please help me overwrite this map image service. I do not need a feature service out of this; I just want to change the symbology of one of the layers in the service.