How to show/check for open ports on Ubuntu Linux

How to show/check for open ports on Ubuntu Linux

Checking for open ports on Ubuntu Linux is an essential part of security administration. Some Linux software works by listening for incoming connections. A simple example would be a web server, which handles user requests whenever someone navigates to a website. As a Linux administrator or user, it’s important to always know which ports of your system are open to the internet. Otherwise, you could be unaware of outside connections being made to your computer, which consumes bandwidth and resources, along with being a potential security hole.

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How to gain access to a MAC whitelist WiFi network

How to gain access to a MAC whitelist WiFi network

MAC address whitelisting sounds like a great way to prevent unauthorized access to your wireless network, but it does not work as well as you might think. The purpose of this guide is to demonstrate exactly how easy it is to spoof a whitelisted MAC address and gain access to a restricted network. In the steps below, you will see how to spoof a MAC address to gain access to MAC whitelisted network on Kali Linux.

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How to mount a remote filesystem over SSH with sshfs

How to mount a remote filesystem over SSH with sshfs

SSH (Secure Shell) is a protocol used to establish an encrypted connection with a remote machine using a client-server model: the ssh server runs on the machine we want to access remotely, while a client is used on the machines from which we want to connect. Thanks to sshfs, we can use an existing SSH connection to mount a remote directory in a secure way, without using additional services like NFS or Samba.

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Ubuntu 20.04: Connect to wifi from command line with Netplan

Ubuntu Server 20.04: Connect to WiFi from command line

In this tutorial, you will learn how to connect to WiFi from command line on Ubuntu using Netplan. While this method can be used on Ubuntu desktop systems with a GUI, it is especially useful if you’re running a headless Ubuntu 20.04 system like a Raspberry Pi or need to connect to Wifi on Ubuntu Server. Follow along with us below as we connect to a WiFi on command line via SSID and network key.

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OpenLiteSpeed change port

OpenLiteSpeed change port

The default listening port for OpenLiteSpeed web server is 8088. Many Linux administrators may be more accustomed to using the typical HTTP listening port 80, and HTTPS port 443. If you already have firewall rules or other settings configured for the typical ports, or just need to switch the listening port for other reasons, it is very easy to do inside of the OpenLiteSpeed web panel. In this tutorial, we will guide you through the step by step instructions of changing the default listening port for OpenLiteSpeed server on a Linux system.

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Ubuntu Static IP configuration

Ubuntu Static IP configuration

This tutorial will deal with Ubuntu static IP address configuration. It will provide the reader with a step by step procedure how to set static IP address on Ubuntu Server via netplan and Ubuntu Desktop using NetworkManager. Static IP address is recommended for servers as the static address does not change as oppose to a dynamic IP address assignment via DHCP server.

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Introduction to Curl

Curl command basics tutorial with examples

Curl is a free and open source software we can use to exchange data with servers using one of the many supported protocols, such as HTTP, HTTPS, FTP, FTP, SFTP. Since Curl is a command line tool, we can use it in our scripts, to automatize repetitive tasks, for example. There are many use-cases Curl can cover. In this tutorial, however, we see some of the most common ones.

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Installing and using the ifconfig command on Debian

How to install missing ifconfig command on Linux

Most of us longtime Linux users have the ifconfig command seared into our brain, after years of repetitive use. It comes as a shock to some when they type the command and are met with an error message (ifconfig command not found). Indeed, the command has become deprecated, but it’s still possible to install ifconfig command.

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Netplan static ip on Ubuntu configuration

Netplan static IP on Ubuntu configuration

In this tutorial, we will discuss a netplan static IP configuration on Ubuntu Linux. Netplan allows for straightforward network IP address configuration using human-readable data-serialization language YAML. The article will also discuss a default Netplan network settings and the location of the Netplan configuration file.

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Linux IP forwarding

Linux IP forwarding – How to Disable/Enable using net.ipv4.ip_forward

It may be necessary to configure Linux IP forwarding on a Linux system in certain scenarios. If the Linux server is acting as a firewall, router, or NAT device, it will need to be capable of forwarding packets that are meant for other destinations (other than itself). Linux uses the net.ipv4.ip_forward kernel variable to toggle this setting on or off.

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Change IP address on Ubuntu Server

Change IP address on Ubuntu Server

You have two options when configuring the IP address on your Ubuntu Server, and that is either a static IP address or DHCP. A static IP address allows you to manually select your IP address by configuring it on the Linux system, whereas DHCP relies on the router or DHCP server to lease you an IP address – either a reserved one or the next available one that is currently free, depending on the setup.

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