H3C S7500 Series Ethernet Switches Operation Manual

Operation Manual – MSTP
H3C S7500 Series Ethernet Switches Chapter 1
MSTP Configuration
1-5
A
B
D
C
Connecting to the
common root bridge
Edge ports
MST region
Port 1
Master port
Alternate port
Designated
port
Port 4
Port 5
Port 3
Port 2
Port 6
Backup port
s Figure 1-2 Port role
X. Port states
Ports can be in the following three states:
z Forwarding state: Ports in this state can forward user packets and receive/send
BPDU packets.
z Learning state: Ports in this state can receive/send BPDU packets.
z Discarding state: Ports in this state can only receive BPDU packets.
Table 1-1 lists possible combinations of port states and port roles.
Table 1-1 Combinations of port states and port roles
Port role
Port state
Root/
port/Mast
er port
Designat
ed port
Region
edge port
Alternate
port
Backup
port
Forwarding √ √ √
— —
Learning √ √ √
— —
Discarding √ √ √ √ √