Troubleshooting Stp; Spanning Tree Protocol Failure - D-Link DGS-3308TG User Manual

Does not add addresses to its forwarding database.
Receives BPDUs, but does not direct them to the system CPU.
Does not receive BPDUs for transmission from the system CPU.
Receives and responds to network management messages.

Troubleshooting STP

Spanning Tree Protocol Failure

A failure in the STA generally leads to a bridging loop. A bridging loop in an STP environment comes from a port that
should be in the blocking state, but is forwarding packets.
8-port Gigabit Ethernet Switch User's Guide
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