Most Linux distributions for years have used the traditional net-tools utilities for command-line network management, but Ubuntu 17.04 Zesty Zapus had abandoned them in favor of the new iproute2 set of utilities. So instead of typing ifconfig to find the IP address of your computer, you instead type ip addr.
That said, if you want to get the old net-tools utilities back, it’s easy to do. Launch a Terminal window by hitting the CTRL+ALT+T keys simultaneously, and then type this command:
sudo apt-get install net-tools
Enter your password, and apt will download and install the net-tools commands. You can then use the traditional commands like ifconfig, route, and arp.
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