STP
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 3000 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 90 second.
GigabitEthernet11 link down
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 80 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 70 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 60 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 50 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 40 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 30 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 20 second.
Port GigabitEthernet11 is automatically blocked by DrayLoop Detection for 10 second.
這個日誌訊息代表居易（DrayTek）VigorSwitch上的 DrayLoop Detection（迴圈偵測）功能被觸發，並自動將 GigabitEthernet11 連接埠封鎖（Block）3000 秒。
這是為了防止網路風暴（Broadcast Storm）導致整個局域網路癱瘓的保護機制。
為什麼會這樣？
1. 實體網路迴圈（Network Loop）： 該連接埠下接的交換機（Switch）或其他網路設備，不小心將兩條網路線互插，或是形成了一個環狀迴路。
2. 廣播風暴： 網路中的封包在迴路中無限循環放大，觸發了VigorSwitch的防護機制。
如何解決？
找出並移除迴路（最重要）
• 檢查 GigabitEthernet11 連接埠 後方連接的所有設備、交換機和網路線。
• 確認沒有任何一條網路線的「兩端都插在同一台交換機上」，也沒有兩台交換機之間同時接了兩條網路線（除非有設定 LACP 聚合）。
• 如果只有單接一個設備，檢查網路線有沒有被老鼠咬了或是浸水