Ansible Server Security: How to Secure Your Ansible Server

Ansible Server Security: How to Secure Your Ansible Server. Harnessing Ansible for automating your operations empowers your organization to seamlessly manage and configure infrastructure, orchestrate complex workflows, and effortlessly deploy applications. Undoubtedly, Ansible is the DevOps darling for software automation, but a caveat comes into play. You see, while Ansible is innately secure, the slightest misconfiguration or misuse introduces vulnerabilities. In this guide, we go over some of the best practices to proactively guard against these vulnerabilities.

Why Ansible Server Security is Important

Securing your Ansible server is crucial for safeguarding your entire infrastructure automation environment. Why? Because Ansible plays a central role in managing and configuring your automation environment. As a result, it has considerable access privileges to critical resources, including servers, devices, and data. Sometimes, it even has access to login credentials and encryption keys. So, failure to secure your Ansible server could open the door to malicious actors.

Ansible Server Security Best Practices

Now that you understand the looming risk, here’s how to secure your server: 

Use the Latest Version of Ansible

When you use the latest version of Ansible, you get access to the most up-to-date security fixes and improvements. Not only does it equip you with the latest features, but also addresses emerging security vulnerabilities and bugs. For this reason, make regular updates to maintain the security, reliability, and compatibility of your automation environment. You may also subscribe to the Ansible Security Announcements to stay up-to-date with the most recent security updates.

Use Ansible Vault

Ansible Vault is a feature that allows you to encrypt sensitive data within your projects. Use it to secure sensitive data such as passwords, SSH keys, and API keys. Ansible Vault uses symmetrical encryption algorithms to protect your data. This means you may only access your data by providing a password. 

To access Ansible Vault, use the ansible-vault command. Here’s how to go about it.

Let’s encrypt a file called my-data.yml (these files typically have a .vault or .yml extension) by running the following command:

					ansible-vault encrypt my-data.yml

You are prompted to enter a password, which is used to encrypt the file. 

To view the file run the following command:

					ansible-vault view my-data.yml

You are prompted to enter the password you used when creating the file.

Protect Against Root Privilege Risks

Ansible playbooks execute tasks on target hosts using the privileges of the user running the playbooks. For this reason, running tasks with root privileges can have serious security consequences. They include:

  • Data Loss: Incorrectly configured tasks could modify or delete critical data, leading to data loss or leakage.
  • Privilege Escalation: If a playbook contains vulnerabilities or mistakes, attackers could exploit them to escalate their privileges to root on the target hosts.
  • System Compromise: Unnecessarily running tasks as root could allow an attacker to compromise your entire system.

Mitigate this risk by creating a dedicated user on target hosts. This user should have only the necessary privileges to execute the tasks in your playbooks. 

Configure Playbooks for Read-Only Access

When you execute an Ansible playbook, Ansible connects to each server in your inventory to perform the tasks defined in the playbook. Typically, it uses SSH for these connections and has full write access to your servers. Consequently, if an attacker gains access to your control server, they also gain write access to all the servers in your inventory. This situation poses a significant security risk since the attacker could take control of your servers.

To safeguard your servers, you need to configure Ansible to operate in read-only mode. In this mode, Ansible only has read access to the servers in your inventory. In the event of an attack on your control server, the attacker wouldn’t be able to manipulate files on the servers in your inventory.

To enable read-only mode, you need to make a configuration change in your ansible.cfg file by adding the following line:


This line instructs Ansible to use the sudo command when connecting to remote hosts. Now playbooks only execute commands with read-only access unless explicitly configured not to.

Use SSH Key Authentication

Passwords pose a security risk to your automation environment. Attackers can guess or “brute force” your passwords or steal them through phishing, data breaches, and other methods.

SSH keys provide a more secure authentication method. They consist of a pair of cryptographic keys – a public key and a private key. The private key is kept secret on your local machine, while the public key is stored on the remote host you want to access. These keys are extremely difficult to crack or guess. Also, using SSH keys is more convenient than entering a password each time you connect to a remote host. Once you’ve set up SSH keys, the authentication process is automatic, and you don’t need to remember or type in a password.

Enable Auditing and Logging

Auditing and logging your Ansible server helps you record and keep track of your automation environment. You can keep an eye on playbook executions, user interactions, and system changes. Detailed logs give you visibility into what’s happening on the server, which is crucial for security monitoring.

To enable auditing and logging, edit the ansible.cfg file on your server. Ensure that logging is enabled and configured according to your requirements. Here’s a sample configuration:

log_path = /var/log/ansible.log
log_file = ansible.log
log_level = INFO

In the example above, the logs are stored in  /var/log/ansible.log with an INFO log level. Adjust the log level to control the level of detail in the logs (e.g., INFO, DEBUG). 

To view the logs, use the following command: 

					cat /var/log/ansible.log

Enable Firewall Rules

Enabling firewall rules on managed hosts helps to protect your environment from malicious network attacks. This process involves using Ansible’s built-in firewall module (firewalld or ufw) to configure and manage firewall rules on remote servers or devices.

Define the desired firewall rules, including what traffic to allow and what to block, in your playbooks. For example, set it up so that only incoming connections from trusted IP addresses or networks access Ansible. This helps minimize the attack surface.

Use a VPN

Establishing a Virtual Private Network (VPN) connection between the Ansible control node and managed hosts helps shield your sensitive data and communication from eavesdroppers. As a result, you reduce the risk of network-based attacks. This added layer of security ensures the confidentiality and integrity of Ansible operations. In addition, it enables secure remote management and the implementation of IP whitelisting to restrict access to trusted entities.

Follow Secure Coding Practices

Using secure coding practices involves adhering to well established guidelines and techniques to minimize the risk of vulnerabilities and security breaches in your codebase. For example, when creating playbooks and roles, you must adhere to secure coding practices of your programming language. This includes sanitizing and validating inputs, encrypting sensitive data, and implementing secure communication channels to protect against potential vulnerabilities.

Security Patch Your Server

Regularly updating and patching your server is critical for maintaining a secure environment for Ansible. Not only does it protect your server, but it also bolsters the security of your automation environment as a whole.

Ansible Server Security: How to Secure Your Ansible Server Conclusion

Finally, Ansible significantly enhances your operational efficiency through automation. However, you must use it with the inherent security risks in mind. By following the best practices we’ve outlined in this guide, you improve and safeguard the security of your projects.

Remember, security is not a one-and-done project; it’s an ongoing process. Make it an integral part of your automation strategy. So, staying vigilant and proactive will ensure that your automation initiatives remain resilient, reliable, and safeguarded against the ever-present security challenges.

Avatar for Richard Kanyoro
Richard Kanyoro

The world’s biggest problems can be solved by progressively solving the little ones. I write to help people solve the “little” tech problems they face.

0 0 votes
Article Rating
Notify of
Inline Feedbacks
View all comments
Would love your thoughts, please comment.x