Access Control

Proper access control ensures only authorized personnel and processes can interact with your node and its resources. This minimizes the risk of insider threats, unauthorized changes, and accidental misconfigurations.

Principle of Least Privilege: This principle states that users and processes should only have the minimal permissions necessary to perform their tasks. For example, if a user only needs to monitor the node’s performance, they shouldn’t have access to configuration files or the ability to restart the node. Implementing this ensures that the attacker's impact is limited even if an account is compromised.

Role-Based Access Control (RBAC): Use RBAC to assign permissions based on the user or service's role. This helps manage access levels efficiently. For instance, developers, administrators, and auditors may each have different access rights, and these roles can be easily managed and modified as needed.

SSH Security: If you access your node remotely, securing SSH access is crucial. Disable password-based authentication and use SSH keys instead. SSH keys are far more secure than passwords and are less susceptible to brute-force attacks. Configure your SSH daemon to turn off root login and listen on a non-standard port to reduce the risk of automated attacks.

Multi-Factor Authentication (MFA): Enable multi-factor authentication (MFA) for all accounts with administrative access for added security. This adds a second layer of protection, requiring a physical device or an additional verification step to access sensitive resources.

Audit and Review: Regularly audit access logs to ensure no unauthorized attempts have been made to access the node. Review user permissions periodically to ensure they are still appropriate for each user's current roles. Remove access for users who no longer require it, such as former employees or contractors.

Privileged Access Management (PAM): For larger setups, consider using a PAM solution to manage privileged accounts and enforce policies like time-based access, where permissions are only temporarily and automatically revoked.

Emergency Access Procedures: Establish a protocol that allows trusted personnel to gain immediate access to the node if needed. Make sure this process is secure and documented to avoid misuse.