Bash Commands

Quick Reference

Bash

sha256sum filename

python3 ./lichess-bot.py -v -u

sudo docker compose up -d

openssl rand -hex 32

# View local & universal time
timedatectl

# Show the total file size of folder
du -sh foldername

# Count the number of lines
wc -l filename

# Monitor the CPU's core temperatures
sensors
watch sensors # live monitoring

# Root access
sudo su # root access on Ubuntu
sudo -i # root access on Ubuntu
su root # root access on other distros

# Restart & Shutdown
sudo init 6 # restart
sudo init 0 # shutdown
systemctl reboot
systemctl poweroff

# Services
sudo systemctl restart apache2
sudo service php8.0-fpm restart # for updating php.ini file

# System utilities
sudo apt-get update --fix-missing
xset m default # mouse speed
units # converter

---

Docker Compose

Bash

sudo docker compose up -d
sudo docker compose down
# Navigate to your project folder containing your docker-compose.yml
sudo docker compose pull

# GUI with DOCKGE
cd /opt/dockge
sudo docker compose up -d
http://localhost:5001

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PC Stats / Info

• TTY Graphical Interface Toggle: Ctrl+Alt with F1/F7 (Ubuntu = F7, RHEL = F1)
• man <command> - Know more about what a command can do
• Flags: -s means summary, -h means human readable

Bash

lspci # pc stats
cat /etc/issue.net # show ubuntu version
uname -a # prints all system information
lsb_release -a # prints Linux version information

history -c # clear all of the past commands
pwd # print working directory
ls -l # list down the directories & files of the current directory
fdisk -l # show partitions
lsblk # list of partition drives
df # displays filesystem disk space usage for all mounted partitions
free -m -h # view free memory in MB (human-readable)
lshw # Hardware Lister

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LAMP: Linux, Apache, MariaDB, PHP

Service Management

Bash

# Apache
sudo systemctl start|stop|restart|reload|status apache2

# MariaDB
sudo systemctl start|stop|restart|status mariadb
sudo mariadb -u root -p

# Check Apache config for errors
sudo apache2ctl configtest

# Enable/disable Apache modules
sudo a2enmod <module>
sudo a2dismod <module>

# Enable/disable Apache sites
sudo a2ensite <site>.conf
sudo a2dissite <site>.conf

MariaDB / MySQL Configuration

Bash

sudo mysql -u root -p # login to mariaDB/mySQL

SQL

SHOW DATABASES;
DROP DATABASE my_database;
DROP DATABASE IF EXISTS my_database;

SELECT User,Host FROM mysql.user; -- show users
DROP USER 'userName'@'localhost';
SELECT database(); -- see/select current database
USE new_database; -- use this database

CREATE DATABASE my_databaseDB;
CREATE DATABASE IF NOT EXISTS my_databaseDB;
CREATE USER user@localhost;
SET PASSWORD FOR user@localhost= PASSWORD("password");
GRANT ALL ON my_database.* TO 'user'@'localhost' IDENTIFIED BY 'password' WITH GRANT OPTION;
FLUSH PRIVILEGES;
EXIT;

Joomla Installation via CLI

Bash

wget [https://github.com/joomla/joomla-cms/releases/Joomla_3.9.12-Stable-Full_Package.zip](https://github.com/joomla/joomla-cms/releases/Joomla_3.9.12-Stable-Full_Package.zip)

sudo mkdir -p /var/www/html/my_website
unzip -q Joomla_3.9.12-Stable-Full_Package.zip -d /var/www/html/my_site

sudo chown -R www-data:www-data /var/www/html/my_site/
sudo chmod -R 755 /var/www/html/my_site/

---

PostgreSQL

Bash

sudo -u postgres psql # access the database

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SSH / FTP

Bash

ssh root@41.185.91.26
ssh root@example.com # IP address version
ssh domainuser@example.com # domain FTP user version

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Network & Processes

Network Interfaces & Diagnostics

Bash

sudo systemctl restart NetworkManager

# View Public IP
curl ipv4.icanhazip.com
wget -qO - [https://api.ipify.org](https://api.ipify.org)
dig +short myip.opendns.com @resolver1.opendns.com

sudo iwlist wlan0 freq # available frequencies
iwlist wlan0 scan

ifconfig
iwconfig
sudo lshw -class network # view details of network/card
ip addr # system's network interfaces
route -n # list kernel routing tables
ip link show # view mac addr
hostname -I # view my IP add

# NetworkManager Client
nmcli # controlling NetworkManager
nmcli dev show | grep DNS # view DNS servers
nmcli connection show
resolvectl status

Network Traffic Monitoring

Bash

bmon # bandwidth monitor and rate estimator
sudo iftop # data flowing through individual socket connections
iptraf # individual connections and data flow amount between hosts
tcptrack # captures packets and calculates bandwidth stats
sudo tcptrack -i eth0/wlan0
vnstat # network traffic monitor (background daemon)
nload # monitor incoming and outgoing traffic separately
nethogs wlan0

netstat -tunap
netstat -i
ss -t -a
ss -a -t -o state established

DNS & Domain Lookups

Bash

whois websiteName
host <IP address>
dig <IP address>
nslookup <IP address>
nslookup –type=mx <domain name> # check for valid email addresses

Nmap Scanning

Bash

man nmap
nmap -A -T4 scanme.nmap.org

Process & Resource Monitoring

Bash

top # real-time active processes ordered list
htop # advanced interactive Linux process monitoring tool
sudo iotop # monitor real-time Disk I/O and processes
sudo iotop -o # only show processes or threads actually doing I/O
lsof # list open files

---

SQLMap

Bash

sqlmap -u "[http://your-target-url.com/vulnerable-parameter?param=value](http://your-target-url.com/vulnerable-parameter?param=value)" --dbs

---

Time-Warrior

Bash

timew --view current state
timew tags # view used tags
timew start "my activity"
timew start myActivity
timew stop
timew continue
timew summary
timew summary myActivity
timew track 9:00 - 11:00 'Outline the tutorial topics' # add forgotten time to log

---

Task-Warrior

Bash

task add "Buy milk" # add a task
task list # see pending tasks
task 1 done # mark task 1 as complete
task 1 modify priority:H # set priority

---

Anti-Virus (ClamAV)

Bash

sudo systemctl stop clamav-freshclam
sudo freshclam # update clamav anti-virus
sudo systemctl start clamav-freshclam

clamscan -r /home # check files in all users home directories
clamscan -r / # scan entire computer

---

OpenVPN

Bash

sudo apt-get install openvpn network-manager-openvpn network-manager-openvpn-gnome

sudo systemctl start openvpn@server
sudo systemctl status openvpn@server

---

Sendmail

Bash

echo "This is a test email." | sendmail tjaart@localhost

Text Only

sendmail user@example.com
From: me@myhost.com
To: user@example.com
Subject: Your subject here

Hi, this is my message, and I'm sending it to you!
.

---

Easter Eggs

Bash

ls /usr/share/calendar/
calendar -f /usr/share/calendar/calendar.pagan -A 365
calendar -f /usr/share/calendar/calendar.music -A 365
calendar -f /usr/share/calendar/calendar.computer -A 365
calendar -f /usr/share/calendar/calendar.history -A 365
calendar -f /usr/share/calendar/calendar.world -A 365

---

Ownership & Groups

Bash

sudo chown owner:group /home/user/filename # change owner and group
sudo chown owner: /home/user/filename # change owner
sudo chown :group /home/user/filename # change group

groups username
groups # view groups
users # view users
compgen -u # view users
compgen -g # view groups

---

File Permissions

Bash

sudo chmod 665 filename
sudo chmod u+x go=rx filename

Octal	Binary	File Mode
0	000	---
1	001	--x
2	010	-w-
3	011	-wx
4	100	r--
5	101	r-x
6	110	rw-
7	111	rwx

• Context Legend: u = user/owner, g = group, o = Other/wOrld
• Permission Legend: r = read, w = write, x = execute

Quick Syntax Examples

• u+x: Add execute permission for the owner
• u-x: Remove execute permission from the owner
• +x or a+x: Add execute permission for the owner, group, and world
• o-rw: Remove read and write permission from anyone besides the owner and group owner
• go=rw: Set the group owner and anyone besides the owner to have read and write permission
• u+x,go=rx: Add execute permission for the owner and set the permissions for the group and others to read and execute

---

Folders & Files Management

Bash

rm -r folder # Remove a folder and its content recursively
mkdir folder # Create a new folder
rmdir folder # Remove an empty folder
rm filename # Remove said filename
cp -i /file/location/fileName /newFile/location/folder/ # copy and ask if to replace
> filename # create blank new file

du -sh folder # show the total file size of folder
wc -l file # count the number of lines

subl /filename # open file with Sublime-Text

---

Archive Extraction

Bash

tar -xvf Package_Name.tar
tar xvzf Package_Name.tar.gz
tar xvjf Package_Name.tar.bz2

gunzip File_Name.gz
7z x Package_name.7z
unzip Package_name.zip -d /path/path/folder

---

Flatpak

Bash

flatpak run org.gimp.GIMP # run flatpak application
flatpak list # list installed applications
flatpak uninstall applicationID
flatpak uninstall --unused
flatpak update # update all applications
flatpak update -v # fix install errors

---

Package Installation & Compilation

Bash

./configure
make
sudo make install

sudo grub-install --root-directory=/mnt /dev/sda

sh fileName.sh
bash fileName.sh

dpkg --list # installed packages
dpkg --status <package name> # determine if package is installed
apt-cache show <package name> # installed package information
dpkg --get-selections | grep -v deinstall # list of installed programs
sudo dpkg -i <package name> # Installing .deb packages

sudo apt-get install -f # install missing dependencies

apt-get remove/purge <program name> # remove/delete program
apt-get -u upgrade # list upgradeable packages

sudo aptitude purge packagename # remove package and configuration files
rpm -Uvh package.rpm # Install an rpm package

---

PPA Repositories

Bash

apt policy # list PPA Repositories
ls /etc/apt/sources.list.d # list PPA Repositories

sudo add-apt-repository --remove ppa:PPA_REPOSITORY_NAME/PPA
sudo apt-get install ppa-purge
ppa-purge ppa:PPA_REPOSITORY_NAME/PPA

---

Formatting USB Storage

Bash

lsblk # list of partition drives
df -h

sudo umount /dev/sdc1
sudo mkfs.vfat /dev/sdc1 # for vfat*
sudo mkfs.ntfs /dev/sdc1 # for ntfs
sudo mkfs.ext4 /dev/sdc1 # for ext4

---

Package Manager Lock Errors (Shitty Error Solved)

Bash

# Find and kill the process holding the lock
ps -e | grep -e apt -e adept | grep -v grep 

sudo dpkg --configure -a # help with the configuration error
sudo rm /var/cache/apt/archives/lock

---

Aircrack-ng (Wi-Fi Security)

Bash

airmon-ng check kill
airmon-ng start wlan0 # monitor mode, receive all network traffic
airodump-ng mon0 # capture packets
airodump-ng -c 9 --bssid DC:EE:06:B4:14:2E -w dump mon0 # capture only one AP (bssid, channel 9)

# Cracking
aircrack-ng -b DC:EE:06:B4:14:2E dump-01.cap -w ../folder # cracking WEP passwords
aircrack-ng dump-01.cap -w /folder/folder/filename.txt # filename.txt is the wordlist

sudo ./wifite.py

• Reference: Null-Byte Wi-Fi Hacking Guide

---

John the Ripper

Bash

# Extract hash from office document
python office2john.py fileName.txt > newFile.txt

# Bruteforce hash file using a wordlist
john --wordlist=wordlistfile/myWordlist.txt hash-file.txt

---

Basic Math Operations

Using the expr command line tool:

Bash

expr 134 + 11 # add
expr 134 - 11 # subtract
expr 134 / 11 # divide
expr 134 \* 11 # multiply (note the \ escape before *)
expr 134 % 11 # remainder

# Logical comparisons (Yes=1, No=0)
expr 134 \> 11 # Is 134 bigger than 11?
expr 134 = 11 # Does 134 equal 11?

Variable Calculations Example

Bash

age=33
expr $age = 33 # returns 1 (yes)

age=33
age=`expr $age + 1`
echo $age # outputs 34

• Reference: Vitux Guide on CLI Math

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Joomla CMS Tweaks & Workarounds

Fix Chmod Verification Error

Open the file libraries/vendor/joomla/filesystem/src/File.php

Find this line of code:

PHP

if (!Path::canChmod($file))

Change it to:

PHP

if (!Path::canChmod($file) && false)

Remove Deprecation Notices from phpMyAdmin

Add the following configuration code to your config.inc.php:

PHP

$cfg['SendErrorReports'] = 'never';

Misc/Uncategorized Hash Signatures

• open = $2y$10$TrqVEcvwTowz0ojvsffUFukN7iC2Mm6gevviCA6UEpG6XLzgufo86