Introduction
The ping command is a network tool for checking whether a remote system is up and running. In other words, the command determines if a certain IP address or a host are accessible. Ping uses a network layer protocol called Internet Control Message Protocol (ICMP) and is available on all operating systems.
On the other hand, port numbers belong to transport layer protocols, such as TCP and UDP. Port numbers help identify where an Internet or other network message is forwarded when it arrives.
In this tutorial, you will learn how to ping a port in Windows and Linux using different tools.
Prerequisites
- A Linux or Windows system
- Access to the command line
- An account with sudo/admin privileges
Can You Ping a Specific Port?
Network devices use ICMP to send error messages and information on whether communication with an IP address is successful or not. ICMP differs from transport protocols as ICMP is not used to exchange data between systems.
Ping uses ICMP packets, and ICMP does not use port numbers which means a port can’t be pinged. However, we can use ping with a similar intention – to check if a port is open or not.
Some network tools and utilities can simulate an attempt to establish a connection to a specific port and wait to see if the target host responds. If there is a response, the target port is open. If not, the target port is closed, or the host is unable to accept a connection because there is no service configured to listen for connections on that port.
How to Ping a Specific Port in Linux?
You can use three tools to ping a port in Linux:
- Telnet
- Netcat (nc)
- Network Mapper (nmap)
See our tutorial on how to use the ping command in Linux to learn about additional ping options and variations in Linux.
Ping a Specific Port Using Telnet
Telnet is a protocol used for interactive communication with the target host via a virtual terminal connection.
1. To check whether telnet is already installed, open a terminal window and enter telnet.
2. If telnet is not installed, install it using the following command
- For CentOS/Fedora:
yum -y install telnet - For Ubuntu:
sudo apt install telnet
3. To ping a port using telnet, enter the following command in the terminal:
telnet <address> <port_number>The <address> syntax is the domain or the IP address of the host, while <port_number> is the port you want to ping.
telnet google.com 443
If the port is open, telnet establishes a connection. Otherwise, it states a failure.
4. To quit telnet, press Ctrl + ] and run the q command.
Note:: Learn how Telnet differs from SSH.
Ping a Specific Port Using Netcat
Netcat (nc) reads and writes from connections using TCP and UDP protocols. This command-line tool can perform many network operations.
1. To check if netcat is installed:
- For Debian, Ubuntu, and Mint: enter
netcat -h - For Fedora, Red Hat Enterprise Linux, and CentOS:
ncat -h
2. If netcat is not installed, run the following command in the terminal:
sudo apt install netcat3. To ping a port using netcat enter the following:
nc -vz <address> <port_number>
The output informs the user if the connection to the specified port is successful or not. If it is successful, the port is open.
Ping a Specific Port Using Nmap
Nmap is a network tool used for vulnerability scanning and network discovery. The utility is also useful for finding open ports and detecting security risks.
Important: Be aware of legal ramifications regarding improper Nmap use, for example, flooding a network or crashing a system.
1. Check if you have Nmap installed by entering nmap -version in the terminal.
If Nmap is installed, the output informs the user about the app version and platform it runs on.
2. If there is no Nmap on your system, enter the following command:
- For CentOS or RHEL Linux:
sudo yum install nmap - For Ubuntu or Debian Linux:
sudo apt install nmap
3. Once Nmap is installed on the system, use the following command to ping a specific port:
nmap -p <port_number> <address>
The output informs the user about the port’s state and service type, latency, and the time elapsed until the completion of the task.
4. To ping more than one port, enter nmap -p <number-range> <address>.
The <number-range> syntax is the range of port numbers you want to ping, separated by a hyphen.
For example:
nmap -p 88-93 google.com
Learn in-depth how to use nmap to scan ports with our guide How To Scan & Find All Open Ports With Nmap.
How to Ping a Specific Port in Windows?
There are two ways to ping a port in Windows:
- Telnet
- PowerShell
Ping a Port Using Telnet
Before using telnet, make sure it is activated:
1. Open the Control Panel.
2. Click Programs, and then Programs and Features.
3. Select Turn Windows features on or off.
4. Find Telnet Client and check the box. Click OK.
You activated the Telnet Client on the system.
After completing the activation, you are ready to ping a port using telnet.
Follow these steps:
1. Search for “cmd” in the start menu. Click the Command Prompt.
2. In the command prompt window, enter
telnet <address> <port_number>The <address> syntax is the domain or the IP address of the host, while <port_number> is the port number you want to ping.
The output lets you know if the port is open and reachable. Alternatively, a connection failure message is shown.
Note: Learn more about Telnet by referring to our guide How To Use Telnet On Windows.
Ping a Port Using PowerShell
PowerShell is a text-based shell that comes with Windows by default.
To ping a port using PowerShell, follow these steps:
1. Search for “PowerShell” in the start menu. Click the Windows PowerShell app.
2. In the PowerShell prompt window enter
Test-NetConnection <address> -p <port_number>
If the port is open and the connection passes, the TCP test is successful. Otherwise, a warning message appears saying the TCP connection failed.
Conclusion
Now you know how to ping and check if a port is open by using several network tools and utilities on Linux and Windows.
Bear in mind that you should not do TCP probing or scan a system unless you have the owner’s permission. Otherwise your actions may be interpreted as an attempt to compromise security.
