You'll need to install an agent on the on-prem machine and only out-bound connections will be needed, so you don't really need to open firewall for in-bound. If you need particular IPs for out-bound rules that might be pretty difficult to summarize at the
moment because it involves a good number of different services.
The data refresh performance is largely dependent on the network latency and bandwidth between your on-prem machine to the Azure data center. We are targeting a 2MB/s throughput for the happy path.
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