ipset

Sudoers first

To create a custom sudoers file in the /etc/sudoers.d/ directory for the user knocknoc-agent, allowing them to run the command /usr/sbin/ipset with any arguments, follow these steps:

1. Create a New File in /etc/sudoers.d/:

   • Choose a meaningful name for the file, such as knocknoc-agent.
   • The command would be sudo visudo -f /etc/sudoers.d/knocknoc-agent.
   • This opens a new file in the sudoers.d directory for editing with proper syntax checking.

2. Add the Necessary Rule:

   • In the editor that opens, add the following line:
     knocknoc-agent ALL=(ALL) NOPASSWD: /usr/sbin/ipset *
   • This line follows the same syntax and meaning as described previously.

3. Save and Exit:

   • Save the file and exit the editor. visudo will automatically check the syntax.

4. Set Correct Permissions:

   • Ensure that the file has the correct permissions. It should be readable by root only and should not be writable by any other user.
   • You can set the appropriate permissions using: sudo chmod 0440 /etc/sudoers.d/knocknoc-agent.

5. Verify the Configuration:

   • To check if your configuration works, switch to the knocknoc-agent user (if possible) and try executing the ipset command with sudo without a password.

Important Notes:

• Always use visudo to edit sudoers files to prevent syntax errors.
• Ensure that the files in /etc/sudoers.d/ have strict permissions (like 0440) to maintain security.
• Be cautious with NOPASSWD: as it allows executing the specified command without a password, which can be a security risk if not properly managed.