Dahua DH-PFS4212-8GT-96 Web Operation Manual page 31

Step 4 Select 3 ports at least to combine an STP/RSTP/MSTP snoop. For example: Port 1, port 2 and
port 3 combine an STP snoop.
Click Save.
Step 5
The states of port 1, port 2 and port 3 will change.
Figure 3-22 MSTP
Figure 3-23 STP snoop
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