[0] https://blogs.nvidia.com/blog/2020/05/12/mellanox-integrated...
All configurations go in a single JSON file, which is used to configure the docker containers that manage the switching hardware.
Here is a cheatsheet:
https://cumulusnetworks.com/learn/resources/cheatsheets/nclu
Also Cumulus runs FRR (as does sonic) but on Cumulus you can do sudo vtysh and pretty much be at a CLI for routing like you are at an IOS prompt.
Sonic sticks all configuration in different docker containers in Json files and can be a real pain. Also not all commands are hitless, ie some will restart forwarding. That is being worked on. SONiC is pretty much “what MS wanted for large scale ops” and still is rough around the edges for enterprise IT.
There are a number of companies that support Sonic in production enterprise such as Dell and Apstra.