mkdir -p /tmp/safezone
mount -t tmpfs -o size=100M tmpfs /tmp/safezone

cd /tmp/safezone
bash suspicious_script.sh

cd /
sudo umount /tmp/safezone

iftop -ni eth0

iftop -P -i eth0

iftop -n -i eth0

iftop -t -i eth0

iftop -o destination
iftop -o source

iftop -F 192.168.0.0/24 -i eth0

apt install nsntrace

# nsntrace --use-public-dns wget -q -O /dev/null https://example.com/
Starting network trace of 'wget' on interface enp1s0.
Your IP address in this trace is 172.19.28.255.
Use ctrl-c to end at any time.
Finished capturing 131 packets.

# nsntrace php -f index.php
Starting network trace of 'php' on interface enp1s0.
Your IP address in this trace is 172.19.213.255.
Use ctrl-c to end at any time.
Finished capturing 52 packets.

# tcpick -r nsntrace.pcap 
Starting tcpick 0.2.1 at 2025-11-15 14:22 MSK
Timeout for connections is 600
tcpick: reading from nsntrace.pcap
1 SYN-SENT 172.19.28.255:40638 > 104.244.78.134:https
1 SYN-RECEIVED 172.19.28.255:40638 > 104.244.78.134:https
1 ESTABLISHED 172.19.28.255:40638 > 104.244.78.134:https
1 FIN-WAIT-1 172.19.28.255:40638 > 104.244.78.134:https
1 FIN-WAIT-2 172.19.28.255:40638 > 104.244.78.134:https
1 RESET 172.19.28.255:40638 > 104.244.78.134:https
tcpick: done reading from nsntrace.pcap

131 packets captured
1 tcp sessions detected

find . -type f -mmin -10

find /var/log -type f -mmin -60

find . -type f -mtime -1

find . -type d -mmin -30

find . -type f -mmin -15 -exec ls -lh {} ;

#!/bin/bash

# Основные параметры
WEB_SERVER="https://example.com"
BACKUP_DIR="/backup"
TARGET_DIRS="/var/www /etc"
DISK_USAGE_THRESHOLD=90
ADMIN_EMAIL="admin@example.com"
DATE=$(date +"%Y-%m-%d")
BACKUP_FILE="$BACKUP_DIR/backup-$DATE.tar.gz"

# Проверка, отвечает ли веб-сервер
echo "Проверка состояния веб-сервера..."
if curl -s --head $WEB_SERVER | grep "200 OK" > /dev/null; then
    echo "Веб-сервер отвечает корректно."
else
    echo "Проблема: веб-сервер не отвечает." | mail -s "Сбой веб-сервера" $ADMIN_EMAIL
fi

# Контроль использования диска
echo "Анализ доступного места на диске..."
DISK_USAGE=$(df / | grep / | awk '{ print $5 }' | sed 's/%//g')
if [ $DISK_USAGE -gt $DISK_USAGE_THRESHOLD ]; then
    echo "Проблема: достигнут лимит использования диска ($DISK_USAGE_THRESHOLD%)." | mail -s "Недостаточно места на диске" $ADMIN_EMAIL
else
    echo "Свободного места достаточно."
fi

# Формирование резервной копии
echo "Запуск создания резервной копии..."
tar -czf $BACKUP_FILE $TARGET_DIRS

if [ $? -eq 0 ]; then
    echo "Резервная копия создана: $BACKUP_FILE"
else
    echo "Не удалось создать резервную копию." | mail -s "Сбой резервного копирования" $ADMIN_EMAIL
fi

# Отправка итогового отчета
echo "Отправка итогового отчета на $ADMIN_EMAIL..."
REPORT="Отчет за $DATE\n\n"
REPORT+="Ответ веб-сервера: $(curl -s --head $WEB_SERVER | head -n 1)\n"
REPORT+="Уровень использования диска: $DISK_USAGE%\n"
REPORT+="Файл резервной копии: $BACKUP_FILE\n"

echo -e $REPORT | mail -s "Системный дневной отчет" $ADMIN_EMAIL

echo "Завершено."

chmod +x /path/to/your/сheck+backup.sh

0 0 * * * /path/to/your/сheck+backup.sh

ss -tulpn

ss -ntp | grep "192.168."

ss -ntp state established

ps -fp <PID>

watch -n 2 ss -tulpn

grep -oE '\b([a-zA-Z0-9-]+\.)+[a-zA-Z]{2,}\b' /var/log/syslog | sort -u

tcpdump -A -s 0 port 80 | grep -oE '\b([a-zA-Z0-9-]+\.)+[a-zA-Z]{2,}\b' | sort -u

ssh -L 8080:internal-server:80 user@gateway

Host myserver
HostName 192.168.1.100
User admin
Port 2222
IdentityFile ~/.ssh/my_key

ssh-copy-id user@server

Host *
ControlMaster auto
ControlPath ~/.ssh/sockets/%r@%h:%p
ControlPersist 600

tar cz folder/ | ssh server "tar xz -C /destination"

ssh server "tail -f /var/log/app.log" | grep -i error

glances

glances -w

glances -s

glances -c IP

glances --browser

nmap -p- -oX baseline.xml 192.168.100.100

nmap -p- -oX current.xml 192.168.100.100

ndiff baseline.xml current.xml

-Nmap 7.80 scan initiated Sat Nov 22 13:32:40 2025 as: nmap -p- -oX baseline.xml 192.168.100.100
+Nmap 7.80 scan initiated Sat Nov 22 13:34:55 2025 as: nmap -p- -oX current.xml 192.168.100.100

192.168.100.100:
-Not shown: 59995 filtered ports, 5538 closed ports
+Not shown: 59994 filtered ports, 5538 closed ports
PORT   STATE SERVICE VERSION
+80/tcp open  http

nohup your_command & disown

folder="~/Documents/photos"
prefix="img_"

cd "$folder"
i=1
for file in *; do
  ext="${file##*.}"
  mv "$file" "${prefix}${i}.${ext}"
  ((i++))
done

IMG1234.jpg, vacation.png, photo_01.jpeg

img_1.jpg, img_2.png, img_3.jpeg

mtr -T --port 443 vpn.example.com

mtr --interval 2 --timeout 10 --report 1.1.1.1

mtr --report --report-cycles 20 example.com

mtr --json 8.8.8.8 > result.json

mtr --aslookup --report example.com

mtr --mpls --report example.com

mtr -n --report 1.1.1.1

mtr -T --port 443 -n --json --report-cycles 15 1.1.1.1