Spanning tree protocol port status: why do you want to have a blocked state? When to go to the listening state?
The blocking state don't study for the address, data forwarding and send bpdus, but will receive bpdus,
However, when just open the STP, all ports in the blocking state, then there is no port sends bpdus,
The blocking state can receive bpdus and what's the point?

thank you

CodePudding user response:

STP working mode is defined, the beginning is blocked,
STP biggest flaw is the slow convergence, often encounter switch boot to tens of seconds to communication, because less of the STP, initial setting for block is to begin a process of convergence, block with aging time 20 s, before entering the listener (temporary state, only deals with bpdus), after the default of 15 seconds to enter the learning state (process bpdus, learn MAC), then after 15 seconds, can enter the forwarding state (initialization and state switch work processes are similar),
In addition, the link status is not permanent, including port forwarding/blocking state, bpdus used to calculate the topology, generate link, so even if the blocking state, also needs to receive bpdus,