Editing the Whitelist
Combine Azure uses a Squid Cache proxy (with SSL interception) to emulate the airgap. The proxy's whitelist is the allowed file on the Combine-Proxy Virtual Machine. This page shows you how to edit it.
Combine and Non-HTTP/S Protocol Proxying
Combine proxies HTTP and HTTPS traffic. Some foundational services, such as Redis, PostgreSQL, and other TCP-based protocols, do not speak HTTP/S, so Combine cannot proxy them directly.