There is no ifconfig command in Ubuntu system
Some of the Ubuntu systems that have just been installed do not have the toolkit installed, so some commands may not be available, such as the ifconfig command.
When such a prompt appears, it means that the ifconfig command is not found, and you can install it. Follow the command in the prompt to install the relevant toolkit
Command:
sudo apt install net-tools //使用apt源安装net-tools工具包
