Linux Skill - Бесплатный курс по Linux c нуля до DevOps.

   sudo mkfs.btrfs /dev/sda1

   sudo mkfs.btrfs -L my_btrfs /dev/sda1

   sudo mkfs.btrfs -m raid1 -d raid1 /dev/sda1 /dev/sdb1

   sudo mkfs.btrfs -n 16384 /dev/sda1

   sudo mkfs.btrfs -l 16384 /dev/sda1

   sudo mkfs.btrfs -M /dev/sda1

   sudo btrfs subvolume create /mnt/my_btrfs_subvolume

$ mkfs.btrfs -m raid1 -d raid1 /dev/sda1 /dev/sdb1

$ btrfs balance start [btrfs mount point]

$ sudo btrfs scrub start /dev/sda1

sudo iptables -L -nv

sudo ip6tables -L -nv

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination

namei -l /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png

f: /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png
drwxr-xr-x root     root     /
drwxr-xr-x root     root     home
drwxr-xr-x himanshu himanshu himanshu
drwxr-xr-x himanshu himanshu Downloads
drwxr-xr-x himanshu himanshu HTF-review
drwxr-xr-x himanshu himanshu Nodejs-Docker
-rw-rw-r-- himanshu himanshu 1.png

namei -o /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png

f: /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png
 d root     root     /
 d root     root     home
 d himanshu himanshu himanshu
 d himanshu himanshu Downloads
 d himanshu himanshu HTF-review
 d himanshu himanshu Nodejs-Docker
 - himanshu himanshu 1.png

   sudo iptables -L -nv --line-numbers

   sudo iptables -I INPUT 7 -p tcp --dport 8080 -m state --state NEW -j ACCEPT

   sudo iptables -R INPUT 9 -m limit --limit 3/min -j LOG --log-prefix "iptables_INPUT_denied: " --log-level 7

   sudo iptables -D INPUT 7

   chown :newgroup filename

   chown newowner:newgroup filename

   chown :newgroup file1 file2 file3

namei -v /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png

f: /home/himanshu/Downloads/HTF-review/Nodejs-Docker/1.png
 d /
 d home
 d himanshu
 d Downloads
 d HTF-review
 d Nodejs-Docker
 - 1.png

namei -l /var/www/your_site_name/htdocs/wp-admin/index.php

f: /var/www/your_site_name/htdocs/wp-admin/index.php
drwxr-xr-x root         root         /
drwxr-xr-x root         root         var
drwxr-xr-x your_username your_group  www
drwxr-xr-x your_username your_group  your_site_name
drwx--x--x your_username your_group  htdocs
drwx------ root         root         wp-admin
-rw-r--r-- your_username your_group  index.php

   ls -a

   ls -la

   ls -a | grep ".conf"

  ls -lh

   su -
   apt-get update
   apt-get install btrfs-assistant

   pkexec btrfs-assistant

sudo apt-get install libpam-google-authenticator

google-authenticator

   pacstrap /mnt base linux linux-firmware nano networkmanager grub efibootmgr

   grub-install --target=x86_64-efi --efi-directory=/boot --bootloader-id=GRUB
   grub-mkconfig -o /boot/grub/grub.cfg

     FROM ubuntu
     CMD ["echo", "Hello, world!"]

     FROM ubuntu
     ENTRYPOINT ["echo", "Hello,"]
     CMD ["world!"]

tar -r --exclude="*.log" /path/to/directory

tar -r archive_name.tar newfile

tar -czvf -9 archive_name.tar.gz /path/to/directory

gzip -tv archive_name.tar.gz

tar -cvf archive_name.tar /path/to/directory

tar -czvf archive_name.tar.gz /path/to/directory

tar -xzvf archive_name.tar.gz

tar -tvf archive_name.tar.gz

# Использование официального образа Python 3.8 как базового
FROM python:3.8

grep [OPTION...] PATTERNS [FILE...]
grep [OPTION...] -e PATTERNS ... [FILE...]
grep [OPTION...] -f PATTERN_FILE ... [FILE...]

$ grep -n -- 'f.*\.c$' *g*.h /dev/null
argmatch.h:1:/* definitions and prototypes for argmatch.c

grep -C 3 "pattern" file

grep --debug "pattern" file

grep "pattern" file > results.txt

grep "ERROR" /var/log/syslog

grep "def " *.py

grep "keyword" dataset.csv

grep "ERROR" /var/log/* | sort | uniq -c | sort -nr

find /path -type f -name "*.txt" -exec grep "pattern" {} \;

grep "pattern" file | awk '{print $2}'

grep "pattern" file | sed 's/old/new/g'

grep -l "pattern" * | xargs rm

find . -type f | xargs grep "TODO" | awk '{print $1}' | sort | uniq

zgrep "error" logfile.gz

cat file | grep "pattern"

grep --text "pattern" binaryfile

grep -n "function" *.py

grep --binary-files=without-match "pattern" directory

grep -a "pattern" binaryfile

grep -m 5 "error" logfile.txt

grep --color=auto "pattern" file

grep --binary-files=without-match --color=auto -m 10 "error" /var/log/*

grep -i "error" logfile.txt

grep -E "error|warning" logfile.txt

grep -r "error" /var/log

grep -r --exclude="*.log" "error" /var/log

grep -r --exclude-dir="backup" "error" /var/log

grep "pattern" file

grep -n "error" logfile.txt

42:This is an error message
73:Another error found here

grep -v "debug" logfile.txt

grep -c "error" logfile.txt

   stages:
     - backup

   backup-job:
     stage: backup
     script:
       - tar -czf backup_$(date +%F).tar.gz /путь/к/данным
       - scp backup_$(date +%F).tar.gz user@backup-server:/путь/к/хранилищу

curl -O https://example.com/file.zip

curl -X POST https://api.example.com/endpoint \
  -H "Content-Type: application/json" \
  -d '{"key":"value"}'

curl -F "file=@/path/to/file" https://upload.example.com

   netstat -tulnp

   netstat -an | grep :80

   netstat -s

   watch -n 1 'netstat -an'

systemctl status nginx.service

systemctl list-units --type=service

systemctl isolate multi-user.target

systemctl get-default

systemctl set-default graphical.target

bash
  /etc/systemd/system/backup.timer
  

ini
  [Unit]
  Description=Запуск резервного копирования

  [Timer]
  OnCalendar=*-*-* 02:00:00
  Persistent=true

  [Install]
  WantedBy=timers.target
  

bash
  systemctl enable --now backup.timer
  

systemctl list-timers

   systemctl status cron

   crontab -e

     0 3 * * * rm -rf /tmp/*

     0 2 * * 0 mysqldump -u user -p database > /backups/db_$(date +\%F).sql

     0 4 * * 0 apt update && apt upgrade -y

crontab -l

* * * * * echo "Cron работает!" >> /tmp/cron.log

file suspicious_file

suspicious_file: ELF 64-bit LSB executable, x86-64, dynamically linked, ...

strings suspicious_file | grep "password"

Default password: admin123

bash
  ghidraRun
  

strace ./suspicious_file

open("/etc/passwd", O_RDONLY) = 3
read(3, "root:x:0:0:root:/root:/bin/bash\n", 40) = 40

gdb suspicious_file

break main
run

   docker run -d --name wireguard-portal -p 8080:8080 ghcr.io/h44z/wireguard-portal:latest

   /etc/wireguard/wg0.conf

   sudo apt install wireguard

   wg genkey | tee privatekey | wg pubkey > publickey

   [Interface]
   PrivateKey = <твой_приватный_ключ>
   Address = 10.0.0.1/24
   ListenPort = 51820

   [Peer]
   PublicKey = <публичный_ключ_клиента>
   AllowedIPs = 10.0.0.2/32

   sudo wg-quick up wg0

   sudo apt install ldap-utils

   ldapsearch -x -H ldap://<ip-сервера> -D "cn=admin,dc=example,dc=com" -W

   ldapsearch -x -b "dc=example,dc=com" "uid=<имя_пользователя>"

du -h /путь/к/папке

du -h /путь/к/папке | sort -h | tail -n 10

du -sh /путь/к/папке

du -h --exclude='*.tmp' /путь/к/папке

#!/bin/bash
# Colors for readability
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
RED='\033[0;31m'
NC='\033[0m' # No Color
echo -e "${GREEN}===== System Monitoring Script =====${NC}"
# 1. CPU Usage
echo -e "${YELLOW}\n>> CPU Usage: ${NC}"
mpstat | awk '/all/ {print "CPU Load: " $3 "% idle"}'
# 2. Memory Usage
echo -e "${YELLOW}\n>> Memory Usage: ${NC}"
free -h | awk '/Mem/ {print "Total Memory: " $2 "\nUsed: " $3 "\nFree: " $4}'
echo -e "Swap:\n"$(free -h | awk '/Swap/ {print "Total: " $2 ", Used: " $3 ", Free: " $4}')
# 3. Disk Usage
echo -e "${YELLOW}\n>> Disk Usage: ${NC}"
df -h | grep '^/dev' | awk '{print $1 ": " $5 " used, " $4 " available"}'
# 4. Network Traffic
echo -e "${YELLOW}\n>> Network Traffic: ${NC}"
ifstat -i eth0 1 1 | awk 'NR==3 {print "RX: " $1 " KB/s, TX: " $2 " KB/s"}'
# 5. Top 5 Memory Consuming Processes
echo -e "${YELLOW}\n>> Top 5 Memory Consuming Processes: ${NC}"
ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%mem | head -n 6
# 6. Top 5 CPU Consuming Processes
echo -e "${YELLOW}\n>> Top 5 CPU Consuming Processes: ${NC}"
ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%cpu | head -n 6
# 7. System Logs Monitoring
echo -e "${YELLOW}\n>> Recent Errors in System Logs: ${NC}"
journalctl -p 3 -xb | tail -n 10
echo -e "${GREEN}===== Monitoring Completed =====${NC}"

git clone https://github.com/junkdog/exabind
cd exabind
cargo build --release
./target/release/exabind

   ls -l

   ls -lh

   ls --color=auto

   ls --group-directories-first

   ls -a

   ls -A

   ls -lS

   ls -lt

   ls -ltr

   ls -ld каталог/

ls -lha --color=auto --group-directories-first

   ps -u

   ps -e

   ps aux

   (reverse-i-search)`ssh': ssh [email protected]

   $ cat /var/log/syslog
   $ less ALT + .  # вставит /var/log/syslog

bash
   sudo apt install zaproxy
   

bash
     zap.sh
     

bash
   sudo apt install libapache2-mod-security2
   

bash
     cd /etc/modsecurity/
     sudo git clone https://github.com/coreruleset/coreruleset.git
     

bash
     sudo cp /etc/modsecurity/coreruleset/crs-setup.conf.example /etc/modsecurity/coreruleset/crs-setup.conf
     

apache
     IncludeOptional /etc/modsecurity/coreruleset/crs-setup.conf
     IncludeOptional /etc/modsecurity/coreruleset/rules/*.conf
     

bash
     sudo systemctl restart apache2
     

clear

alias cls='clear && echo "Терминал очищен"'

echo 'clear' >> ~/.bash_profile

#!/bin/bash
echo "Начало работы скрипта"
sleep 2
clear
echo "Продолжаем выполнение..."

printf "\033c"

cksum file.txt

if [[ $(cksum file1.txt) == $(cksum file2.txt) ]]; then
 echo "Файлы идентичны"
else
 echo "Файлы различаются"
fi

#!/bin/bash
for file in /path/to/directory/*; do
 cksum "$file" >> checksums.txt
done
echo "Контрольные суммы всех файлов сохранены в checksums.txt"

while read -r line; do
 current_sum=$(cksum "$(echo "$line" | cut -d' ' -f3)")
 if [[ "$line" != "$current_sum" ]]; then
  echo "Изменение в файле: $(echo "$line" | cut -d' ' -f3)"
 fi
done < checksums.txt

chmod 755 script.sh

chmod u+rwx,g+rx,o-r script.sh

#!/bin/bash
for file in /path/to/directory/*.sh; do
 chmod 755 "$file"
 echo "Права доступа для $file установлены на 755"
done

chmod -R 750 /path/to/directory

ls -l script.sh

stages:
  - build
  - deploy

build-job:
  stage: build
  script:
 - echo "Сборка приложения..."
 - ./build-script.sh

deploy-job:
  stage: deploy
  script:
 - echo "Деплой на сервер..."
 - ./deploy-script.sh

sudo gitlab-runner register

variables:
  DEPLOY_KEY: "ssh-rsa AAAAB3NzaC1yc2..."

gitlab-runner verify

git push origin main

   name: CI/CD Pipeline

   on:
     push:
       branches:
         - main
     pull_request:
       branches:
         - main

   jobs:
     build:
       runs-on: ubuntu-latest

       steps:
       - name: Checkout code
         uses: actions/checkout@v2

       - name: Set up Node.js
         uses: actions/setup-node@v2
         with:
           node-version: '14'

       - name: Install dependencies
         run: npm install

       - name: Run tests
         run: npm test

       - name: Build
         run: npm run build

#!/bin/bash

directory="/path/to/directory"
newgroup="newgroup"

find $directory -type f -not -group $newgroup -exec chgrp $newgroup {} \;
echo "Group of new files in $directory changed to $newgroup"

chmod +x auto_change_group.sh
crontab -e

*/15 * * * * /path/to/auto_change_group.sh

#!/bin/bash

if [ $# -ne 3 ]; then
 echo "Usage: $0 <newgroup> <directory> <username>"
 exit 1
fi

newgroup=$1
directory=$2
username=$3

find $directory -type f -user $username -exec chgrp $newgroup {} \;
echo "Group of all files owned by $username in $directory changed to $newgroup"

chmod +x change_group_by_user.sh
./change_group_by_user.sh newgroup /path/to/directory username

#!/bin/bash

if [ $# -ne 2 ]; then
 echo "Usage: $0 <newgroup> <directory>"
 exit 1
fi

newgroup=$1
directory=$2

chgrp -R $newgroup $directory
echo "Group of all files and directories in $directory changed to $newgroup"

chmod +x change_group_recursive.sh
./change_group_recursive.sh newgroup /path/to/directory

#!/bin/bash

if [ $# -ne 3 ]; then
 echo "Usage: $0 <newgroup> <directory> <pattern>"
 exit 1
fi

newgroup=$1
directory=$2
pattern=$3

find $directory -type f -name "$pattern" -exec chgrp $newgroup {} \;
echo "Group of all files matching $pattern in $directory changed to $newgroup"

chmod +x change_group_by_pattern.sh
./change_group_by_pattern.sh newgroup /path/to/directory "*.txt"

sudo apt update
sudo apt install zabbix-server-mysql zabbix-frontend-php zabbix-agent

CREATE DATABASE zabbix CHARACTER SET UTF8 COLLATE UTF8_BIN;
CREATE USER 'zabbix'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON zabbix.* TO 'zabbix'@'localhost';
FLUSH PRIVILEGES;

sudo nano /etc/zabbix/zabbix_server.conf

DBHost=localhost
DBName=zabbix
DBUser=zabbix
DBPassword=password

sudo nano /etc/zabbix/apache.conf

sudo systemctl restart apache2

sudo apt install smartmontools

sudo systemctl enable smartd
sudo systemctl start smartd

bash
   sudo nano /etc/zabbix/zabbix_agentd.conf
   

   UserParameter=smartctl.discovery,sudo /usr/sbin/smartctl --scan-open | awk '{print "{\"{#DISKNAME}\":\""$1"\"}"}' | jq -s '{"data":.}'
   UserParameter=smartctl.health[*],sudo /usr/sbin/smartctl -H /dev/$1 | grep -i "SMART overall-health self-assessment test result" | awk '{print $6}'
   

sudo apt update
sudo apt install zabbix-server-mysql zabbix-frontend-php zabbix-agent

CREATE DATABASE zabbix CHARACTER SET UTF8 COLLATE UTF8_BIN;
CREATE USER 'zabbix'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON zabbix.* TO 'zabbix'@'localhost';
FLUSH PRIVILEGES;

sudo nano /etc/zabbix/zabbix_server.conf

DBHost=localhost
DBName=zabbix
DBUser=zabbix
DBPassword=password

sudo nano /etc/zabbix/apache.conf

sudo systemctl restart apache2

sudo chattr +i /path/to/file

sudo chattr -i /path/to/file

sudo chattr +a /path/to/file

sudo chattr -a /path/to/file

sudo chattr +s /path/to/file

sudo chattr +i /etc/important.conf

lsattr /path/to/file

alias proj='cd ~/projects'
alias docs='cd ~/Documents'

function go_back() {
    cd "$OLDPWD"
}