What do Instances Mean in Terms of Cloud Computing?
A cloud instance is a virtual machine that runs your workloads in the cloud.
An instance is much like a physical server. However, it is not dependent on hardware or one single data center location.
You use a cloud platform to provision the instances remotely. Some cloud computing platforms include AWS, Google Cloud, and Azure.
You can choose the instance capacity for your workloads. It includes components such as CPU, memory, network, etc.
The cloud platform also offers different cloud computing models. It comes in a public cloud, private cloud, or hybrid cloud services.
This article will focus on instances in cloud computing, its types, and the instance life cycle.
What is an Instance in Cloud Computing -
Define Instance: A cloud instance is a virtual server in a cloud computing environment. It is built and delivered by cloud platforms such as Amazon Web Services. A cloud platform offers computing resources & services.
What is the definition of Instance?
The instances are on-demand and can spin up & down based on your requirements. You decide on the instances’ CPU, GPU, RAM, and other compute resources.
One instance can host a workload or use a group of instances in a cluster.
You can spread out the instances in different geographical regions. In AWS, these are called Regions and Availability Zones.
The cloud provider also categorizes the instances based on use cases.
In AWS, the instance comes with different purchasing options. It depends on your specific requirements.
The primary AWS instance purchasing options include:
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On-Demand Instances – Pay for computing are capacity by the second.
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Dedicated Instances – Pay by the hour, for instance, running on single-tenant hardware. The hardware is dedicated to a single customer.
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Savings Plans – Use the instance consistently for 1 or 3 years.
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Reserved Instances – Use the instance types and Region consistently for 1 to 3 years.
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Spot Instances – Request unused instances to reduce the Amazon EC2 costs.
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Dedicated Hosts – Dedicated Host is a physical server with instance capacity fully dedicated to your use.
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Capacity Reservations – Reserve capacity for instances in a specific Availability Zone.
Cloud workload definition: A cloud workload refers to the tasks, applications, or services that run on cloud-based resources, such as virtual machines or containers, to perform specific functions or operations.
Different Instance Types
The cloud instance type offers different compute, memory, and storage capabilities.
You have to choose an instance type based on your application requirements.
1. Standard or General Instances
The general purpose instance types are configured for standard use. It is the most common instance type for web servers and microservices.
They deliver an optimum balance of resources for your applications. The CPU, memory allocated are balanced for a wide range of general-purpose workloads.
These are well suited for:
- Application servers
- Microservices
- Gaming servers
- Midsize data stores
- Caching fleets
- App development
- Websites and web applications
For example, General-purpose instances in AWS include – A1, M5, M5a, M4, T3, T3a, T2.
2. High CPU Instances
The high CPU instances are built to provide high computing power. It is used for compute-intensive workloads.
The instances offer high performance. The allocated resources are compute-optimized.
Some of the workloads may include:
- High-performance computing (HPC)
- Gaming servers
- Batch processing
- Ad serving
- Video encoding
- Scientific modeling
- Distributed analytics
- CPU-based machine learning
- Graphics rendering
The AWS Compute instances include C5, C5n, C6g, C6gd, and C6gn.
3. High Memory Instances
High memory instances are designed for running memory-intensive workloads.
They deliver fast performance for workloads that process large data sets in the memory. You also have storage optimized instances.
Some of the high memory workloads include:
- High-performance databases
- Real-time data ingestion
- Big data analytics
- Running distributed in-memory caches
- Memory-intensive enterprise applications
The AWS high memory instances include R5, R5a, R5b, R5n, R6i, X1, etc.
4. Instances With GPU
Instances with GPUs provide resources for deep learning. It comes with thousands of computing cores. Training new models is faster on a GPU instance than on a CPU instance.
Some of the workloads include:
- Data-intensive machine learning algorithms
- Data processing
- Virtual Reality applications
- Fluid dynamics
- 3D rendering, Animation
- Autonomous vehicles
- Blockchain computations
The Amazon EC2 instances for GPU include G5, G4ad, and G4dn, G3, P3, P4.
What is an Instance Group
An instance group is a collection of virtual machine instances managed as a single entity. It has the same machine type, image, and the same configuration.
Instance groups are easier to configure and manage. You can add policies & rules to many resources & instance families.
It includes regular updates and high availability configurations. You can configure auto-healing and load balancing policies.
It is also efficient to manage instance groups in specific availability zones.
You can opt for managed instance groups. That way, the updates & scaling are done automatically.
In unmanaged instance groups, you do not get features such as autoscaling or auto-updates.
Instance Life Cycle
1. Provisioning
In this stage, the instances are prepared to enter the running state. The computing resources are allocated & configured at this stage.
You can add the rules & policies for the resources based on your workloads. However, the instances are not running yet.
In AWS, the instances have a pending state. Such instance states are launched for the first time or started after the stopping stage.
2. Running
In this stage, the instances are running and ready for use. You can start hosting the workloads on the instances.
If there are multiple instances, the new instance shares the workloads of the running instances. In AWS, you are billed for the instances in the running stage.
3. Shutting Down
In some cases, the instance may fail a status check or not run as expected. In this stage, the instance is prepared to shut down.
You can initiate the shutting down to fix the instance problem & restart the service.
When it enters the shutting down state, you can modify specific attributes of the instance.
You are not billed for the shut-down state, but charges may incur in EBS storage volume.
4. Terminated
You can delete an instance when you no longer require it. It is called the termination state of the instance.
You change the status of the instance to shutting down or terminated.
As soon as the instance is terminated, you stop incurring charges.
When an instance terminates, the data on any instance store volumes are deleted.
You can use termination protection for your instances. It prevents the instances from being terminated accidentally.
Conclusion
A virtual server instance helps run your workloads.
The cloud platform offers the operating system and hardware of a server. You get storage, CPUs, and pre-loaded application server software.
Cloud instances offer the compute capacity from different data centers. It allows for more infrastructure flexibility & scale.
The instances are easy to scale up & down based on customer demands.
To learn more about cloud computing, check out the CloudPanel blog.
