Comprehensive Guide to Linux (CentOS 7) Installation, Configuration, and Basic Commands

1. Introduction to Linux

Linux is an open‑source, Unix‑like operating system known for its stability, security, and flexibility, widely used on servers and by personal users.

1.1 Common Linux Distributions

Red Hat Enterprise Linux

Fedora

CentOS

Ubuntu

1.2 Obtaining Linux

CentOS can be downloaded directly from the official website or from mirror sites such as Alibaba Cloud:

https://mirrors.aliyun.com/centos/

https://mirrors.aliyun.com/centos-vault/

2. Installing CentOS 7 in a Virtual Machine

2.1 Deploy Virtualization Software

The guide uses VMware Workstation; install the software and create a new virtual machine.

2.2 Configure Virtual Machine Settings

Set CPU, memory, disk, and network options (bridge, NAT, or host‑only) according to the desired connectivity.

2.3 Load and Install the CentOS Image

During boot, edit the boot parameters to disable predictable network interface names:

net.ifnames=0 biosdevname=0

Proceed through the installer, configure partitions (/boot, swap, /), set the root password, and finish the installation.

3. Basic CentOS 7 Commands

3.1 Command Prompt Formats

[root@host ~]#   // superuser prompt
[kang@host ~]$   // normal user prompt

3.2 Common Commands

pwd : display current directory pwd

cd : change directory cd /etc

mkdir : create directories mkdir -p /var/log/app

touch : create empty files or update timestamps touch file.txt

ls : list directory contents ls -la

cp : copy files or directories cp source.txt dest.txt

mv : move or rename files mv oldname.txt newname.txt

rm : remove files or directories rm -rf /tmp/old

3.3 System Management

Use shutdown , reboot , halt , or poweroff to control system power state, and systemctl to manage services such as firewalld and network .

4. Troubleshooting and Optimization

4.1 Common Issues

Permission problems – add Everyone rights to the host folder.

Virtual machine shows a black screen – reset Winsock ( netsh winsock reset ) or adjust BIOS settings.

Remote connection failures – verify network configuration, firewall status, and SSH settings.

4.2 System Optimizations

Disable firewalld and SELinux temporarily for easier setup.

Replace default YUM repositories with faster domestic mirrors.

Set the timezone to Asia/Shanghai and enable NTP synchronization with chrony .

Improve SSH login speed by disabling GSSAPI authentication and DNS lookup.