gcfg | read INI-style configuration files | Configuration Management library

I just figured out the answer myself. There was absolutely nothing wrong with my configuration. Opening up all the TCP ports in my security group was a bit overkill maybe and entirely unnecessary, so don't do that.

The issue was that the corporate network I am connected to blocks outbound traffic to external hosts on certain non-standard ports.

If you're in the same boat as me and need to host 2 services on the same EC2 instance but don't know which ports are unavailable/blocked by your organization then you could use nmap and portquiz.net to figure it out.

nmap is a port scanner and portquiz.net is a service that listens for connections on all TCP ports. You could scan the host using nmap over a range of TCP ports you're interested in using and see which ports show up as open

Per the documentation: "section corresponds to a struct field in the config struct". You should be reading into a struct with a field Server (to take the server section). That field could be of type ServerConfig:

Connect uses a sandbox that uses the same mechanisms as Docker to hide certain directories from executable user code. You'll need to run the container in "privileged" mode. Try doing docker run --privileged ...

I'm not sure I've understood the meanings of the variables in your question, but following code is for the case where first dimension length(x) == second dimension length(y) == third dimension length(z) == 4. It converts linear index i into indices for each dimension: first_index, second_index, third_index, fourth_index.