Before starting knockd, closeport 22960 and try to log in remotely.
在启动knockd之前，关闭端口22960并尝试远程登录。
2
In this case, because you just wanted to open or closeport 22960, a single command sufficed.
在这里，因为只希望打开或关闭端口22960，所以使用单一命令就够了。
3
The last scheme for adding security to your machine is the boldest one. You will close the open port making your machine virtually impregnable to any attack.