This manual introduces Linux system administration for users who are new to managing a Linux system. It covers basic concepts, tools, and procedures needed to keep a Linux system operational.
The document is organized into chapters such as an introduction, a Linux system overview, directory tree description, disk and storage usage, memory management, boot and shutdown, init process, login/logout, user account management, backup, timekeeping, and a glossary of terms. This manual is written in Chinese.
You can back up files with the tar command as described in the backup chapter.
The date command shows the current date and time and can also be used to set the software clock.