linux-notes

Notes and tips in regard to Linux installation, configuration and maintenance.

Current OS

• Ubuntu 22.04 LTS

Must-Install Packages

zsh

• Install Zsh

sudo apt install zsh

chsh
/bin/zsh

• Install Oh My Zsh via Gitee Mirror

wget https://gitee.com/mirrors/oh-my-zsh/raw/master/tools/install.sh
REMOTE=https://gitee.com/mirrors/oh-my-zsh.git BRANCH=master sh install.sh

• Edit ~/.zshrc to enable common plugins (such as docker) and include any startup scripts

Docker

• Install Docker Engine on Ubuntu

  • Use a mirror
  • After installation, edit /etc/docker/daemon.json to use a Docker Registry Mirror, which is usually vendor-specific, such as https://mirror.ccs.tencentyun.com provided by Tencent Cloud.

• Post-installation steps for Linux, e.g., run docker commands as a non-root user

• Install Docker Compose V2 on Linux

Configurations

• Configure Git

git config --global credential.helper 'store'
git config --global user.name "octopusthu"
git config --global user.email octopusthu@gmail.com

• Set timezone

mv /etc/localtime /etc/localtime.backup
ln -s /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

# Change to 24hr format (need re-login)
localectl set-locale LC_TIME=en_GB.UTF-8

• Set hostname (For packages like sendmail to function)
  • hostnamectl set-hostname example.com
  • In /etc/hosts, assign the just updated hostname example.com to 127.0.0.1

SSH

• Basic config

sudo vim /etc/ssh/sshd_config
    Port xxxxx
    PasswordAuthentication no
sudo systemctl restart sshd

• Login using a non-root user with an RSA key via a customized port

client

ssh-keygen -t rsa

server

su - zy
mkdir ~/.ssh
vim ~/.ssh/authorized_keys
    pub key content
chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys
vim /etc/ssh/sshd_config
    Port xxxxx
    PasswordAuthentication no
    PermitRootLogin no
systemctl restart sshd

Unattended Upgrades

• UnattendedUpgrades
  • Need the sendmail package to send notifications via email

Archive

History OS

• CentOS 7
• CentOS 8
• Ubuntu 20.04 LTS
• Ubuntu 21.10