In this post i will shed some light on some spanning-tree info that has been floating around. But also an explanation why i choose a non-obvious answer to an IPexpert question. Specifically 2 things. The first one is the selection of ports and what _exactly_ selects the root port.
Flex Links, otherwise known as the devil for your L2 network. In all fairness, lets actually figure out what this feature is used for. The most important thing you need to know is the fact that Flex links disable your spanning-tree process.