Ubuntu18.04.3 LTS first experience

install the system##

It was too slow to install the virtual machine. There was just an old computer, which was the entire Ubantu system.

Startup disk tool: UltraISO, a veteran tool.

Download the ISO image file on the official website:

https://cn.ubuntu.com/download

Choose long-term stable support version:

Dell computer, F12 enters bios, the installation system may be a bit slow. Then if the black screen report scheme_error keeps looping. Don't worry, it's normal. Just wait a while.

The installation of Ubuntu is much more friendly than other Linux systems. Before I wanted to play CentOS, I still reported various errors after mounting /dev/sda. I struggled for two days and gave up. The online tutorial on Ubuntu is quite reliable.

Change software source##

Open the software and update the application, and replace it with Alibaba Cloud's software source.

About apt and apt-get

APT is a package management system, and then apt-cache, apt-config, apt-get and other commands are derived. Because the commands are too scattered, apt is introduced, apt=apt-get+apt-cache+apt-config.

apt is a simplification of the three commands, but relatively speaking, the apt command cannot cover all commands such as apt-get. But basically it can meet most of the needs.

It is recommended to quickly familiarize yourself with apt and then learn apt-get when necessary. (Apt-get has not been abandoned)

Refer to this article: https://blog.csdn.net/liudsl/article/details/79200134

About apt update and apt upgrade

Generally speaking, it is to update the software.

Linux updates software through sources. Every LINUX distribution, such as UBUNTU, maintains its own software warehouse. Almost all the software we commonly use is in it. The software inside is absolutely safe and can be installed normally. This repository is the installed software source.

The source list contains some URL information.

The function of apt update is to update all the software sources, that is, all the URLs of the local warehouse are updated, but it does not download and install.

The function of apt upgrade is to compare the installed software with the latest software source, and if it can be updated, then update it.

Reference article: https://www.jianshu.com/p/bb9d139fd352

Command line and graphical switching shortcuts##

ctrl + f3/f4/f5/f6 are all OK, the Internet says that f1 and f2 are also OK, but the actual measurement is not good.

Then say alt + f7 can switch to the graphical interface, but no response when pressed.

ctrl+alt+f2 is fine.

Shutdown and restart commands##

shutdown -r now

reboot