Ubuntu Commands for Web Servers: A Web Developer’s Cheat Sheet

Introduction

As a web developer, having the right set of tools is crucial. When it comes to Ubuntu Commands for Web Servers, knowing the right commands can save you time and system resources. This article aims to provide you with the most useful Ubuntu commands for effective web server management.

Understanding sudo

The sudo command allows you to run programs with the security privileges of another user, typically the superuser (root). For example:

sudo apt-get update

This command updates the package list on your system, a task usually reserved for the superuser.

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File and Directory Operations

Navigating and manipulating the file system is a daily task for any web developer. Here are the essential commands to perform these operations.

List directory contents

ls

Change directories

cd

Copy files or directories

cp

Move or rename files and directories

mv

Remove files or directories

rm

Create empty files

touch

Create directories

mkdir

Change file permissions

chmod

Change file ownership

chown

These commands are essential for navigating and manipulating your server’s file system.

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System Information

Monitoring your system’s health is crucial for effective web development. These commands will help you keep an eye on your system.

Display system information

uname

Report file system disk space usage

df

Estimate file space usage

du

Display the amount of free and used memory

free

Display dynamic real-time system status

top

Keep an eye on your system’s health with these useful commands.

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Package Management

For software package management, the following commands are indispensable. They offer a way to add, remove, and manage the software on your system.

APT package handling utility

apt-get

Query the APT cache

apt-cache

Package manager for Debian

dpkg

Efficiently manage your software packages with these commands.

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Network Operations

Network operations are critical for any web server. Use these commands to monitor and manage them.

Check network connectivity

ping

Network statistics

netstat

Display or configure network interfaces

ifconfig

These are your go-to commands for monitoring and managing network operations.

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MySQL Operations

Database management is a key aspect of web development. These MySQL commands allow you to efficiently manage your databases.

Log into MySQL

mysql -u root -p

Create new database (schema)

create database [dbname]

Create a new MySQL user

create user '[username]'@'localhost' identified by '[password]'

Grant privileges to the new user

grant all privileges on [dbname].* to '[username]'@'localhost'

List all databases, show all databases

show databases

Select a database

use [database]

List tables in the selected database

show tables

Exit MySQL

exit

Manage your MySQL databases efficiently with these commands.

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SSH Operations

Secure your server and optimize remote operations with these SSH commands.

Connect to a Server via SSH

Connect to a server via SSH, where [username] is root or your own SSH user and [hostname] is typically your server’s IP address:

ssh [username]@[hostname]

example:

ssh root@yourserverIPaddress

Create a New SSH User

Once connected with a superuser, you can create a new SSH user:

adduser [username]

Generate SSH Keys for the New User

Now, switch to the new user’s account and generate SSH keys:

su - [username]
ssh-keygen

Follow the prompts to complete the key generation. This will create a new SSH key, using the provided email as a label.

Disable the SSH Root User

For security reasons, it is recommended to disable your SSH root user:

sudo passwd -l root

Restart SSH Service

After disabling the root user, it’s a good practice to restart the SSH service:

sudo systemctl restart sshd

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UFW Cheat Sheet = Firewall Operations

UFW is an abbreviation for Uncomplicated Firewall.

The below commands are not necessarily based on a step by step guide.

Check the Firewall Status: To see the current rules, you can use:

sudo ufw status

Enable UFW

sudo ufw enable

This will list all the rules that are currently active.

Allow SSH Connections

sudo ufw allow ssh

Deny All Incoming Connections by Default

sudo ufw default deny incoming

Allow All Outgoing Connections by Default

sudo ufw default allow outgoing

Allowing Specific IPs: If you want to only allow SSH traffic from a specific IP address, you can do:

sudo ufw allow from YOUR_IP_ADDRESS to any port 22

Delete the general OpenSSH rule: You’ll first need to identify the rule number. To do this, run:

sudo ufw status numbered

Delete the Rule: Use the rule number to delete it.

sudo ufw delete [rule_number]

Deny All Other SSH: To deny all other SSH traffic, you can use:

sudo ufw deny 22

Enable/Disable Rules: Any changes you make won’t be active until you enable them:

sudo ufw enable

If you ever need to disable the firewall for troubleshooting, you can do:

sudo ufw disable

Reload UFW: For the changes to take effect.

sudo ufw reload

Please make sure you are very careful when altering firewall rules, especially over SSH, as it’s possible to lock yourself out of your own server if not done correctly.

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Systemctl Operations

Start a service

systemctl start [service]

Stop a service

systemctl stop [service]

Restart a service

systemctl restart [service]

Check the status of a service

systemctl status [service]

Manage system services and units effectively with these systemctl commands.

Conclusion

Having this cheat sheet of Ubuntu commands can significantly ease your web server management tasks. For more tips like this, feel free to follow me on Twitter.

Something missing?

If you think I missed something or looking for something specific, feel free to comment on the article and let me know.