Introduction.
In the ever-evolving world of cloud infrastructure, Amazon Web Services (AWS) has become a cornerstone for building highly scalable, resilient, and efficient systems. One of the most powerful features AWS offers is Auto Scaling, allowing businesses to automatically adjust their EC2 capacity in response to real-time demand. Whether you’re handling fluctuating web traffic, batch processing, or mission-critical workloads, Auto Scaling ensures you’re only paying for the compute power you need when you need it.
At the heart of Auto Scaling lies a crucial decision: how will your EC2 instances be configured and launched? This choice determines not just what type of virtual machines are spun up, but also how efficiently and securely they operate in production. AWS offers two primary methods to define these configurations Launch Configurations and Launch Templates. For many teams, the difference between these two can seem minor or even negligible, especially when both accomplish the basic goal of launching EC2 instances within Auto Scaling Groups (ASGs).
However, the differences are not just technical they’re strategic. Your choice affects not only what features are available to you today, but also how adaptable and future-proof your infrastructure will be tomorrow. While Launch Configurations have been around since the early days of AWS Auto Scaling, they’ve quietly taken a backseat in recent years. In fact, AWS has deprecated Launch Configurations as of 2023, signaling a clear shift in direction. New features, performance improvements, and security enhancements are now being rolled out exclusively to Launch Templates.
If you’re still using Launch Configurations in your stack, you may be limiting yourself in terms of flexibility, cost optimization, and access to newer EC2 capabilities. For example, Launch Templates support advanced features like mixed instance types, Spot Instance configurations, versioning, parameter overrides, and IMDSv2, none of which are available in Launch Configurations. These aren’t just “nice to haves” they’re critical tools for modern DevOps and cloud-native engineering practices.
But the shift to Launch Templates isn’t just about embracing new tools it’s about adopting a mindset of infrastructure evolution. Cloud environments thrive on automation, adaptability, and continuous improvement. Launch Templates are designed with this philosophy in mind, offering a level of granularity, repeatability, and control that legacy Launch Configurations simply can’t match.
In this blog post, we’ll break down the key differences between Launch Configurations and Launch Templates, explore the benefits of migrating, and show you why making the switch isn’t just a recommendation it’s a necessary step toward optimizing your AWS environment for the future. Whether you’re an AWS newcomer or a seasoned architect managing hundreds of instances, understanding this distinction could make a big difference in your system’s performance, cost-efficiency, and operational flexibility.
So, let’s dive deep into EC2 Launch Templates vs Launch Configurations and see why it matters more than ever in today’s cloud-first world.
What Are Launch Configurations?
Launch Configurations were the original method of specifying how EC2 instances should be launched within an Auto Scaling Group (ASG). They allow you to define:
- AMI ID
- Instance type
- Key pair
- Security groups
- Block device mappings
- User data
Once a launch configuration is created, it’s immutable meaning you can’t modify it. You must create a new one and update your ASG if you need to change anything.
Important: As of 2023, AWS has deprecated launch configurations. While they still work for now, you can no longer create them in many regions.
What Are Launch Templates?
Launch Templates are the modern, flexible replacement for Launch Configurations. They offer all the same settings and much more:
Key Features:
Versioning
You can create multiple versions of a template, making it easy to roll back or test changes without creating an entirely new template.
Support for Newer Features
Launch Templates support:
- T2/T3 Unlimited
- Placement groups
- Capacity reservations
- Elastic GPU
- Nitro Enclaves
- Mixed instance policies in Auto Scaling Groups
- Detailed monitoring and tagging on launch
Parameter Overrides
You can override parameters like instance type or AMI when launching, without touching the base template.
EC2 Spot Instances
Full support for configuring and managing Spot Instances, including the use of Spot Fleet and Auto Scaling strategies.
Instance Metadata Options
Control access to the instance metadata service (IMDSv2) for enhanced security.
Key Differences: Launch Templates vs Launch Configurations
| Feature | Launch Configurations | Launch Templates |
|---|---|---|
| Versioning | No | Yes |
| Immutable | Yes (immutable) | Yes (via versioning) |
| Mixed Instance Types | No | Yes |
| Spot Instances Support | Limited | Full support |
| New EC2 Features | Not supported | Supported |
| IMDSv2 Support | No | Yes |
| Ease of Use | Basic | Advanced & Flexible |
| Deprecation Status | Deprecated | Current & Actively Supported |
Why It Matters
1. Future-Proofing Your Infrastructure
AWS is continuously adding new features but only to Launch Templates. If you want access to the latest in instance configuration, Launch Templates are the only option.
2. Smarter Auto Scaling
Launch Templates enable Mixed Instances Policies in Auto Scaling Groups, which let you run multiple instance types and purchase options (On-Demand + Spot) to optimize cost and availability.
3. Enhanced Security
Want to enforce IMDSv2 to prevent SSRF attacks? You can’t do that with Launch Configurations. Launch Templates give you modern security options like metadata access control.
4. Easier Maintenance and Rollbacks
Launch Template versioning lets you roll back a change with a few clicks or lines of code no need to recreate and reassign new configurations each time.
Should You Migrate?
Yes. If you’re still using Launch Configurations, AWS strongly recommends migrating to Launch Templates.
Migration is straightforward:
- Create a Launch Template with the same settings.
- Update your Auto Scaling Group to use the new template and version.
- Optionally delete the old launch configuration.
Final Thoughts
Launch Templates are not just a replacement they’re a major upgrade to how you manage EC2 deployments. Whether you’re managing a large fleet of instances or just getting started with auto scaling, using Launch Templates ensures you’re building on modern, secure, and scalable AWS infrastructure.
As AWS continues to evolve, embracing Launch Templates is the smart move for both performance and operational efficiency.