linux essential commands

linux.md

Linux

NginX

Setup -

# Install
sudo apt-get install nginx

# Enable
sudo ufw allow 'Nginx HTTP'

# Status
systemctl status nginx

Config -

server {
    server_name www.site.com site.com;
		listen *:80;
	
		# Static
		root /var/www;
  
    # Dynamic
    location / {
        proxy_pass http://127.0.0.1:8000;
    }

		# Route
		location /api/ {
       proxy_pass http://127.0.0.1:3002;
       proxy_set_header X-Real-IP  $remote_addr;
       proxy_set_header X-Forwarded-For $remote_addr;
       proxy_set_header Host $host;
    }
}

# Subdomain
server {
        server_name api.site.com;
        location / {
          proxy_http_version 1.1;
          proxy_pass http://127.0.0.1:3000;
          proxy_set_header X-Real-IP  $remote_addr;
          proxy_set_header X-Forwarded-For $remote_addr;
          proxy_set_header Host $host;
          rewrite ^/api/?(.*) /$1 break;
		    }
}

Blocks -

# Create block
touch /etc/nginx/sites-available/example.com

# Link
sudo ln -s /etc/nginx/sites-available/example.com /etc/nginx/sites-enabled/

# Restart 
sudo systemctl restart nginx

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SSL

Certbot

Delete

certbot delete

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Screen

# create screen 
screen -S <name>

# exit screen 
CTRL + A => D

# resume screen 
screen -r <sid>

# kill screen 
CTRL + D

# screen list
screen -ls

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Disk mount

If you can't access the drive, execute the following command:

sudo ntfsfix /dev/sdXY

where XY is the partition

e.g sda2 or sdb1

Then, mount with:

sudo mount -o rw /dev/sdXY

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GPG Tool

sudo apt-get install gnupg

File encryption

gpg -c filename

File decryption

gpg filename.gpg

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PM2

• Install

npm i -g pm2

• Start

pm2 start app.js --name my-api

• Cluster mode

# Start maximum processes with LB depending on available CPUs 
pm2 start app.js -i 0 

# Scales app up by 3 workers
pm2 scale app +3  

# Scales app up or down to 2 workers total
pm2 scale app 2 

• List

# Display all processes status pm2 jlist # Print process list in raw JSON pm2 prettylist # Print process list in beautified JSON
pm2 list 

# Display all informations about a specific process
pm2 describe 0 

# Monitor all processes
pm2 monit 

• Logs

# Display all processes logs in streaming 
pm2 logs [--raw] 

# Empty all log files pm2 reloadLogs # Reload all logs
pm2 flush 

• Actions

# Stop all processes pm2 restart all # Restart all processes
pm2 stop all 

# Will 0s downtime reload (for NETWORKED apps)
pm2 reload all 

# Stop specific process id pm2 restart 0 # Restart specific process id
pm2 stop 0 

# Will remove process from pm2 list 
pm2 delete 0

# Will remove all processes from pm2 list
pm2 delete all 

• Misc

# Reset meta data (restarted time...) 
pm2 reset

# Update in memory pm2
pm2 updatePM2  

# Ensure pm2 daemon has been launched
pm2 ping  

# Send system signal to script
pm2 sendSignal SIGUSR2 my-app 

pm2 start app.js --no-daemon 

pm2 start app.js --no-vizion 

pm2 start app.js --no-autorestart

pm2 start [echo.py](http://echo.py/)

pm2 start "pipenv run python -m scripts.script1"

pm2 start test.bash --interpreter bash

---

Processes

top

lsof -i:PORT

kill -9 PSID

nohup cmd &> output &

---

Script record

Start

script ./output.txt

Stop

exit

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Port

UFW

Enable

sudo ufw enable

Default port

sudo ufw allow 22

Status

sudo ufw status

Open port

sudo ufw allow 5500

UFW guide

DO guide

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Docker

Run compose in bg

docker compose up -d

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Disk fix

fsck /dev/sda5

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