The complexity of application environments makes automating configuration management essential for every organisation. However, would you prefer an agent-based or agentless configuration management software?

For most organisations, getting started with automation is a daunting task. Most first decisions centre on selecting an automation tool, with most of these tools falling into one of two categories: agent-based or agentless.

A configuration manager agent is both a powerful and complex automation tool that can be agent-based or agentless. Regardless of what you end up choosing, they are both vital in managing applications and infrastructures.

In this article, you’ll learn about configuration management and the differences between an agent-based and agentless configuration management tool.

What is Configuration Management

Typically, configuration management refers to a systems engineering approach to ensuring consistency in a project’s specifications. However, in the IT world, it refers to the process of monitoring individual system components. Every IT system comprises a wide variety of IT assets, packages, and components. It can be a single piece of software, server automation tools, or a version control system.

Configuration management is the systematic process of tracking, managing, and maintaining consistency in software and system configurations to ensure reliability, security, and performance across an IT environment. It involves version control, automation, and monitoring of changes to configurations, ensuring that systems remain in a known and desired state while minimising errors and inconsistencies. It’s typically used together with CI/CD infrastructure and version control software.

Essentially, configuration management tools help developers build stable, robust, and secure systems. In addition to this, it helps to monitor & manage configuration updates initialised in the configuration metadata.

With the number of assets in a project or microservices, it’s often easy to relegate configuration parameters to an afterthought. As a result, configuration management ensures a single source of truth or a central repository for all configuration information. Git is an example of this.

By storing configuration data in a Git repository, you can manage & track versions and rely on it as the source of truth. Through version control, you can anticipate breaking changes and consequently reduce downtime. Version control and configuration management systems allow you to view changes to configurations in real time. Developers can review, roll back, or reverse the changes made to configuration files through the version control system.

Comparing Agent-based and Agentless Configuration Management: Agent vs Agentless

The complexity of developing applications rises as organisations adopt containerised microservices and data centres. As a monitoring tool, agent-based environments deploy monitoring software on all servers across the entire architecture. The agents collect data using a variety of APIs and system calls. Afterwards, review log files, as well as other proprietary sources. A central monitoring server then receives the information from these agents, tabulates the results, checks thresholds and alarms, and provides users with the results.

Agentless environments, however, use a single configuration manager agent to monitor the entire infrastructure. As a result, the term “agentless” may be a bit misleading. The central server monitors infrastructure devices via APIs, SSH, and system interfaces to determine performance and availability. You can use this agent to manage and handle server operations throughout your network.

With a management dashboard, you can view real-time application data, development history, and alerts, among other metrics.

The Argument For Agent-based Configuration Management

In some arguments, performance monitoring has always been cited as a top reason for choosing agent-based configuration tools. It provides deeper and wider monitoring than agentless configuration management tools. Some of the other benefits agent-based architecture has over agentless architecture include:

• Lower bandwidth requirement: Agent-based architecture reduces bandwidth requirements by collecting data locally and only transmitting processed results. Agents can also preprocess Data locally before sending it to the server, thus reducing the processing load on the remote server, which is already handling requests from multiple Agents.
• Security: There is an increasing focus on security and its necessity in the development process. It’s one disadvantage of agentless environments. Agentless configuration management software has a single vulnerability point. If it ever falls victim to an attack, a hacker can have unlimited access to all applications and servers. In addition, security concerns also arise when using protocols such as SSH and WinRM at scale to manage large numbers of machines. Most Agent-based setups utilise SSL to ensure that data is encrypted in Transit. Agentless systems perform this as well, but the user can easily change the system configuration, causing it to be less secure.

The Case For Agentless Configuration Management

With agent-based configuration management, it’s impossible to get information about an application’s current state or to enforce the desired state for optimal operation and performance. For example, an uninformed user may modify the machine to the extent that it suffers a security vulnerability, not noticing it until the very last minute.

Now, let’s take a look at the benefits that agentless configuration management tools offer:

• Enhanced performance: Agentless architectures provide better maintenance and efficiency while using fewer resources, less memory, and requiring no additional installation.
• Faster Deployment: One primary advantage of agentless architectures is the speed of deployment. For agent-based solutions, it’s necessary to deploy software to every server, which can take a considerable amount of time. With agentless, you can centrally deploy and configure applications.
• Lower costs: This is by far the most significant reason for choosing agentless configuration management software. Having individuals on every VM in a network increases administration costs, CPU & bandwidth consumption, and communication overhead. With an installed agent on every VM, users will incur additional costs when installing updates. By introducing an agentless architecture, you’ll be saving time and costs in scaling, investigating network issues, and patching.

The Best Solution To Configuration Management

Managing infrastructure and applications is often a tedious task due to their complexity. Because of this, selecting the best configuration management tools can be equally taxing. For example, if you intend to manage a set of servers — virtual or physical— with heavy workloads and tasks, AttuneOps is a suitable solution.

AttuneOps is a server management solution that provides you with a modern & easy-to-use interface for server management. Other benefits include reduced deployment time, higher security, document generation, automated build procedures, integrated file support, and task scheduling.

Agent Vs Agentless Configuration Management: Frequently Asked Questions