Hello I am new at networking and studying for CCNA.
There is a paragraph like this in the book and I am struggling about understanding well. Maybe it's because english is not my native language.
spanning-tree vlan x root primary (on the switch that should be primary)
spanning-tree vlan x root secondary (on the switch that should be secondary)
These two commands cause the switch to make a choice of priority value but then store the chosen priority value in the spanning-tree vlan x priority value command. The command with root primary or root secondary does not appear in the configuration. When configuring root primary, the switch looks at the priority of the current root switch and chooses either (a) 24,576 or (b) 4096 less than the current root’s priority (if the current root’s priority is 24,576 or less) to the configuration instead. When configuring, root secondary always results in that switch using a priority of 28,672, with the assumption that the value will be less than other switches that use the default of 32,768, and higher than any switch configured as root primary.
Can anyone please explain that paragraph to me? What are the logic of those numbers? It kinda made me confused.