Kali and Linux

What is /dev/sda1

• /dev/: The directory containing all device nodes. In Linux, "everything is a file," so hardware components like hard drives, terminals, and mice are represented as files here.
• sd: Originally stood for "SCSI Disk." Today, it is a generic prefix for almost all non-IDE block storage, including SATA SSDs, HDDs, and USB drives.
• a: Indicates the order in which the drive was detected. The first drive is sda, the second is sdb, the third is sdc, and so on.
• 1: Indicates the first partition on that specific drive

The file must be mounted first, /dev/sda1 is used as the EFI System Partition or the /boot partition, which contains the files needed to start the computer.

Linux version:

cat /etc/os-release

lsb_release -a


Configured DNS

cat /etc/resolv.conf

Listening ports:

netstat -tunlp

 

    -t: TCP    -u: UDP    -n: numeric, no name    -l: listening    -p:  Programs


Bounce interface:
ifconfig eth0 down
ifconfig eth1 up

Default route

ip route show

route


IP address

ip addr

• 
  
•  Default login:
  kali
  kali

default login in EVE-NG: root/toor

• Basic Linux Commands:
  pwd
  cd
  ls
  mkdir, rmdir
  cp, rm, mv, locate
  updatedb
  passwd
  man
  
  

         echo "Hi!" > test.txt

• Commands
  chmod
  adduser
  /etc/passwd,/etc/shadow
  su    (switch user)
  sudo 
  
  ifconfig
  iwconfig
  arp
  netstat
  route
  
  
  
  
• View, create and edit files
  echo
     echo "Hi!" > test.txt
  cat
  replacing vs appending (> vs >>)
  touch 
  nano  vi or vim)
  gedit (N/A)
  
  
• start and stop Kali Services
  services
     service apache2 start/stop
     alternative to launch a webserver to transfer file, run in a directory, then from browser will see directory file list
     python -m SimpleHTTPServer [portnumber]
  
  systemctl  (start server permanently)
  systemctl enable ssh
  systemctl enable postgresql
  
  
• Installing
  installing updates with apt-get
     apt-get update && apt-get upgrade
     apt-get install git
   or tools with apt-get
  git  (github)
  
  
• script
  grep
  cut
  tr
  script writing
  for loops
  
  example:
  ping 192.168.2.1 -c 1 > ip.txt
  cat ip.txt
  cat ip.txt | grep "64 bytes"
  cat ip.txt | grep "64 bytes" | cut -d " " -f 4      (-d delimiter, -f field)
  cat ip.txt | grep "64 bytes" | cut -d " " -f 4 | tr -d ":" 
  
  

#! /bin/bash
if [ "$1" == "" ]
then
echo "you forgot an ip address"
echo "Syntax:  ./ipsweep.sh 192.168.1"
else
for ip in `seq 1 254` ; do
ping -c 1 $1.$ip | grep "64 bytes" | cut -d " " -f 4 | tr -d ":" &
done
fi

./ipsweep.sh 192.168.2 > iplist.txt

for ip in $(cat iplist.txt); do nmap -sS -p80 -T4 $ip & done

https://www.thecybermentor.com/

https://www.hackthebox.com/

https://www.virtualhackinglabs.com/

https://www.vulnhub.com/

Nessus

======Linux=====

Sudo stands for SuperUser DO and is used to access restricted files and operations. By default, Linux restricts access to certain parts of the system preventing sensitive files from being compromised.

The sudo command temporarily elevates privileges allowing users to complete sensitive tasks without logging in as the root user.

back to last directory I was 

cd -      

back to home directory

cd ~

clear screen
clear or Ctrl+L

Backgroup and frontgroup

Example, when in vi, need switch to terminal, Ctrl+Z, in Terminal, type fg to go back vi

call back last command with sudo 

sudo !!

History commands
history
!xxx

=========

To simulate a network behind your Ubuntu machine, you should create a dummy interface instead of modifying the existing lo loopback. A dummy interface behaves exactly like a loopback but allows you to assign unique, non-local routing subnets (like 192.168.50.1) that can simulate an external network.

Temporary Setup (Resets on Reboot)

Use these commands to quickly create an interface named dummy0 and assign an IP address to simulate your target network.

bash

# 1. Load the dummy kernel module
sudo modprobe dummy

# 2. Create the new dummy network interface
sudo ip link add dummy0 type dummy

# 3. Assign your simulated network IP address to the interface
sudo ip addr add 192.168.50.1/24 dev dummy0

# 4. Bring the interface up
sudo ip link set dev dummy0 up

Permanent Setup (Persists After Reboot)

Modern Ubuntu versions (18.04 and newer) use Netplan for persistent network configuration.

1. Force the dummy module to load at boot:
   bash

   echo "dummy" | sudo tee -a /etc/modules
   

   
   
2. Open your Netplan configuration file:
   Find your configuration file name inside /etc/netplan/ (it usually ends in .yaml, such as 01-netcfg.yaml).
   bash

   sudo nano /etc/netplan/01-netcfg.yaml
   

   
   
3. Add the dummy interface configuration:
   Append the dummies section to your file. Ensure your indentation uses spaces, not tabs.
   yaml

   network:
     version: 2
     renderer: networkd
     dummies:
       dummy0:
         addresses:
           - 192.168.50.1/24
   

   
   
4. Apply the changes:
   bash

   sudo netplan apply
   

   
   

Verify the Interface

Run the following command to verify your new simulated network interface is active and holding the correct IP:

bash

ip addr show dummy0