AWS has a wide array of instance types and lifecycle options available, making it easy to find the best fit for your specific application. While there are some variations from Lifecycle Manager to EC2, there are four basic types of instance lifecycle in AWS:
On-Demand Instances:
On-demand instances are the simplest way to use AWS instances. They are immediately available and billed by the hour by your account (or minute with certain instance types). You can create as many as you need, and you can easily scale up or down as your needs change. The main advantage of using on-demand instances is that they provide flexibility and scalability out of the box.
Reserved Instances:
A reserved instance is a committed payment for an instance and involves a discount when compared to the On-Demand cost. This option offers two models: an upfront payment for a one-year or three-year term, or a smaller upfront payment that’s billed monthly for the duration of the term. Reserved instances provide cost savings of up to 75% compared to on-demand prices, with even greater discounts when multiple instances are purchased.
Spot Instances:
Spot instances are instances that are purchased at a discounted rate when they’re offered by AWS. These instances may become available when AWS needs to free up capacity, and they are sold at a discounted rate that varies according to supply and demand. The biggest benefit of using spot instances is the potential reduction of compute costs, especially when running batch or task-oriented workloads.
Dedicated Hosts:
Dedicated hosts are physical servers that are dedicated to your workloads. This option provides complete control over the placement of your instances, allowing you to run complex workloads such as license-restricted software, PCI/HIPAA-compliant workloads, and more. It also lets you choose the exact hardware configuration that best suits your needs. The only downside of this option is the high cost associated with renting the dedicated hosts.
Each of these AWS instance lifecycles has its pros and cons and merits consideration according to your specific application. For example, if you require strict control over resources and placement, then dedicated hosts are essential. If your workload requires lower costs, then spot instances are a great option. Regardless of your needs, understanding the different types of instance lifecycles available in AWS is an important step in successfully leveraging its services.
