Editor’s note: HP Software recently announced the launch of six free network utilities. This series of blog posts provides short overviews of how each tool can help you manage your network.
One of your most important jobs for any network administrator is confirming that network attached devices are configured to keep attack vulnerabilities to a minimum.
Scanning TCP ports on a target host goes a long way to help secure a corporation’s critical network service, allowing administrators to discover open ports on devices and close these backdoors that would-be attackers could exploit to gain access.
The new HP Network Port Scanner is a straightforward tool that easily and clearly identifies used and unused ports on a target host. This data can then be validated against any internal policies concerning open ports an organization may have.
What it does
The network port scanner tool uses the connect scan technique, a standard method that attempts to establish full TCP/IP connections sequentially through all ports on a given host, and a very accurate way to determine which TCP services are accessible.
Working with the tool
The tool is distributed in the form of a runnable jar file, which should be copied to a folder and run by an admin from that location on a Windows platform by clicking on the jar. (On a Linux run the following command: java –jar <Network_Port_Scanner.jar>)
This will launch the GUI (Figure 1). The user enters the IP Address of the remote host that he or she needs to scan, selects whether TCP or UDP are to be scanned, and enters the port range (ex. 1 – 65535).
By clicking the scan button, the tool generates two tables that list and identify the Used Ports and Unused Ports (Figure 2).
The results can also be exported to .csv file once the scan is complete, simply by selecting the Save option from the File Menu.
Currently, the tool completes 65,000 ports at approximately 5-6 minutes on the localhost, although the speed of the network and machine could also impact the great response time this tool provides.
To read other posts about how these free tools work, check out the Business Service Management blog and watch for our next post, which looks at the HP VMWare Reporter tool, and how you can use it to report on VMware datacenters, ESX hosts, virtual machines, and distributed virtual switches.