When designing a highly available architecture, what is the difference between vertical scaling (scaling-up) and horizontal scaling (scaling-out)?
Click on the arrows to vote for the correct answer
A. B. C. D.Correct Answer - C.
In high availability architectures, Autoscaling is used to give elasticity to the design.
Horizontal scaling (scaling-out) uses Autoscaling groups to increase processing capacity in response to changes in preset threshold parameters.
It could involve adding more EC2 instances of a web server.
Vertical scaling (scaling-up), which can create a single point of failure, involves adding more resources to a particular instance to meet demand.
https://docs.aws.amazon.com/autoscaling/plans/userguide/what-is-aws-auto-scaling.htmlOption A is INCORRECT.
Scaling-up does not provide high availability.
Adding more resources to one instance is often not a best-practice in architecture design.
Option B is INCORRECT.
Scaling-out is cost-effective since it involves adding more resources in response to demand and reducing resources (scaling down) when demand is low.
Option D is INCORRECT.
All Autoscaling groups require a launch configuration based on what resources would be provisioned or deprovisioned to meet predefined parameters.
When designing a highly available architecture, scaling is an essential factor to consider to ensure that the system can handle increasing traffic and workload demands. There are two types of scaling: vertical scaling (scaling up) and horizontal scaling (scaling out).
Vertical scaling involves adding more resources such as CPU, memory, and storage capacity to a single server or instance. This type of scaling is often referred to as "scaling up" because it increases the power of a single machine.
Horizontal scaling, on the other hand, involves adding more instances or servers to distribute the workload across multiple machines. This type of scaling is also referred to as "scaling out" because it increases the number of machines in the system.
Now let's go over the options:
A. Scaling up provides for high availability whilst scaling out brings fault-tolerance. This answer is incorrect. Both scaling up and scaling out can contribute to high availability and fault-tolerance. However, the approaches differ in how they achieve this.
Vertical scaling (scaling up) can provide high availability by adding more resources to a single server, which can help the server handle higher loads without crashing. But, vertical scaling does not inherently provide fault-tolerance since all resources are concentrated on a single machine, and if it fails, the entire system goes down.
Horizontal scaling (scaling out) provides fault-tolerance by spreading the workload across multiple instances, and if one instance fails, the other instances can take over the load. Horizontal scaling can also provide high availability by allowing the system to handle more traffic since there are more instances available to process requests.
B. Scaling out is not cost-effective compared to scaling up. This answer is also incorrect. In general, horizontal scaling (scaling out) can be more cost-effective than vertical scaling (scaling up) since it relies on commodity hardware, which is often less expensive than high-end hardware used for vertical scaling. Additionally, scaling out provides greater flexibility since you can add or remove instances as needed, whereas scaling up requires replacing hardware with more powerful components, which can be costly.
C. Scaling up adds more resources to an instance, scaling out adds more instances. This answer is correct. As explained earlier, vertical scaling (scaling up) adds more resources to a single instance, while horizontal scaling (scaling out) adds more instances to the system.
D. Autoscaling groups require scaling up whilst launch configurations use scaling out. This answer is incorrect. Both autoscaling groups and launch configurations can be used for either vertical scaling (scaling up) or horizontal scaling (scaling out). Autoscaling groups can scale out by adding more instances to the group based on traffic demand, and launch configurations can be used to create multiple instances with the same configuration. Both approaches can be used for vertical scaling by increasing the resources of a single instance.