Linux command
knock 命令
文本
复制后可按需替换文件名、目录或参数。
常用示例
Knock on a sequence of ports
knock [hostname] [port1] [port2] [port3]
Knock
knock [hostname] [port]:tcp [port]:udp
Knock using UDP
knock -u [hostname] [port1] [port2] [port3]
Knock with a delay
knock -d [500] [hostname] [port1] [port2]
Display verbose
knock -v [hostname] [port1] [port2] [port3]
说明
knock is the client component of port knocking. Port knocking is a security technique where a firewall opens specific ports only after receiving a predefined sequence of connection attempts ("knocks") on closed ports. The client sends packets to the specified ports in sequence. When the server (knockd) detects the correct sequence, it executes configured commands, typically to open a firewall port for the client's IP address.
参数
- -u, --udp
- Use UDP instead of TCP
- -4
- Force IPv4
- -6
- Force IPv6
- -v, --verbose
- Display verbose information
- -d, --delay _MS_
- Delay between knocks in milliseconds
FAQ
What is the knock command used for?
knock is the client component of port knocking. Port knocking is a security technique where a firewall opens specific ports only after receiving a predefined sequence of connection attempts ("knocks") on closed ports. The client sends packets to the specified ports in sequence. When the server (knockd) detects the correct sequence, it executes configured commands, typically to open a firewall port for the client's IP address.
How do I run a basic knock example?
Run `knock [hostname] [port1] [port2] [port3]` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
What does -u, --udp do in knock?
Use UDP instead of TCP