We recently upgraded to ArcGIS Pro 2.8 and our notebooks that connect to ArcGIS Online have stopped being able to access our proxy host. We've tested in same environment with older install of Pro (2.7) and it works.
We've got a support call in, but it's not getting very far, how would I find out whether there were changes to the proxy host section of the GIS function?
gis = GIS("https://[org].maps.arcgis.com", "[username]", "[password]",proxy_host="dcsproxy.desqld.internal", proxy_port=8080)
ConnectionError: A connection error has occurred: HTTPSConnectionPool(host='[org].maps.arcgis.com', port=443): Max retries exceeded with url: /sharing/rest/generateToken (Caused by ProxyError('Cannot connect to proxy.', OSError(0, 'Error')))
Peter T, Brisbane