1. A system, comprising: a plurality of compute nodes respectively comprising at least one processor and a memory that together implement a system deployment manager that performs one or more system updates to system resources implemented at a private network, wherein the private network is disconnected from outbound communication in order to isolate the private network from external networks; the system deployment manager, configured to: for a given system deployment to update one or more system resources implemented at the private network: generate one or more feedback codes for the given system deployment, wherein the one or more feedback codes are generated to satisfy one or more communication restrictions for a feedback communication channel for the private network, wherein the feedback communication channel is isolated and disconnected from the private network; send the system deployment including the one or more feedback codes via a one-way inbound connection through an external network from the system deployment manager to the private network in order to initiate performance of the update to the one or more system resources implemented at the private network; receive an indication of at least one of the feedback codes for the given system deployment, wherein the at least one feedback code is communicated via the feedback communication channel for the private network; and based, at least in part, on the received indication of the at least one feedback code, determine a current status of the system deployment.