Linux commands to keep your server secure: essential skills and best practices

Linux Commands to Keep Your Server Secure: Essential Skills and Best Practices

As a server administrator, keeping your server secure is one of our top priorities. . In Linux systems, using some necessary security commands and best practices can strengthen the server's defense capabilities.

Below, we will introduce some commonly used Linux commands and provide code examples to help administrators master and apply these commands to ensure the security of the server.

1. Check the system log

The system log is a record of server operation and an important source for discovering potential problems and security threats. Administrators can use the following command to view the system log:

tail -f /var/log/syslog

The above command will dynamically display the contents of the syslog file, and the administrator can monitor the running status of the server at any time.

2. Manage users and permissions

Properly managing users and permissions is the key to maintaining server security. Administrators can use the following commands to manage users and permissions:

• Create new user:

sudo adduser newuser

• Delete user:

sudo deluser username

• Modify user password:

sudo passwd username

• Assign user permissions:

sudo usermod -aG groupName username

3. Firewall configuration

Firewall Is an important tool for protecting your server from unauthorized access. Administrators can use the following commands to configure and manage the firewall:

• View the firewall status:

sudo ufw status

• Enable the firewall:

sudo ufw enable

• Disable firewall:

sudo ufw disable

• Open specific ports:

sudo ufw allow port_number

4. Update and upgrade packages

Keeping the packages on the server up to date is an important aspect of staying secure. Administrators can update and upgrade packages using the following commands:

• Update package list:

sudo apt update

• Upgrade packages:

sudo apt upgrade

• Clean up expired packages:

sudo apt autoremove

5. Use key login

Key login is more secure than password login, administrator You can use the following commands to configure and use key login:

• Generate key pair:

ssh-keygen -t rsa

• Copy the public key to the server:

ssh-copy-id username@server_ip

6. Back up data regularly

Data backup is an important aspect of server security. Administrators can use the following command to back up data regularly:

• Create Data backup:

sudo tar -czvf backup.tar.gz /path/to/backup_folder

• Restore Data backup:

sudo tar -xzvf backup.tar.gz -C /path/to/restore_folder

7. Encrypt files and directories

Protect sensitive files and Directory data security, administrators can use the following commands to encrypt files and directories:

• File encryption:

gpg -c filename

• File decryption:

gpg filename.gpg

• Directory encryption:

tar -czvf - directory_name | gpg -c > backup.tar.gz.gpg

• Directory decryption:

gpg -d backup.tar.gz.gpg | tar -xzvf -

The above are several commonly used Linux commands that can help administrators Keep your server secure. Of course, there are more commands and best practices to explore and apply in actual use.

As a server administrator, constantly learning and mastering these commands and practices will help us better protect the server and ensure its safe operation.

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