dotprobe

Dotprobe is a network diagnostic tool used to test the reachability of a specific port on a remote host. It is particularly useful for network administrators and engineers to troubleshoot connectivity issues, verify firewall rules, and ensure that services are accessible over the network. The tool sends a probe to a specified IP address and port, and it reports whether the port is open, closed, or filtered. This information can help identify network configuration problems, such as misconfigured firewalls or incorrect routing settings.

Dotprobe operates by sending a TCP SYN packet to the target port and waiting for a response. If the port is open, the target host will respond with a SYN-ACK packet, indicating that the port is reachable. If the port is closed, the target host will respond with a RST (reset) packet. If no response is received, the port is considered filtered, which may indicate the presence of a firewall or other network security device.

The tool is available for various operating systems, including Linux, Windows, and macOS, and can be used from the command line. It is a valuable asset for network diagnostics and is often used in conjunction with other network tools to perform comprehensive network assessments. Dotprobe is particularly useful in environments where network security and service availability are critical, such as data centers and enterprise networks.