How would you describe AWS?
Amazon Web Services: consists of a number of cloud-based computing solutions that Amazon provides to its clients
What is “the cloud” or “cloud computing” and why is it so popular now?
- “The cloud” refers to the infrastucture/platform/services hosted by a third-party that can be accessed remotely by clients
- Cloud computing allows developers to take advantage of a large scale computing infrastructure without having to deal with the cost and maintenance of keeping their own servers on premises, i.e. it is a more cost effective way of deploying an application
Define Infrastructure, Platform, and Software as a Service
- IaaS, or infrastructure as a service, is on-demand access to cloud-hosted physical and virtual servers, storage and networking - the backend IT infrastructure for running applications and workloads in the cloud.
- PaaS, or platform as a service, is on-demand access to a complete, ready-to-use, cloud-hosted platform for developing, running, maintaining and managing applications.
- SaaS, or software as a service, is on-demand access to ready-to-use, cloud-hosted application software.
What’s the difference between a Region and an Availability Zone (AZ)?
Availability zones = the individual data centers where the cloud infrastructure is hosted
Region = a grouping of a number of local availability zones that defines certain capabilities/limits of a service within that region
How are you charged for using AWS services? Does it vary by service?
AWS pricing is similar to how you pay for utilities like water and electricity.
You only pay for the services you consume, and once you stop using them, there are no additional costs or termination fees.
What are the different ways to interact with AWS services?
- RDS = relational database as a service
- EC2 = virtual machines to be used on cloud servers
- AMI = configuration for launching an instance of EC2
- EBS = block storage that can be shared across EC2 instances
- Security groups = client control over the traffic to their EC2 instances
What are the configuration options for EC2?
(Note: configuration is defined by the AMI)
- OS
- vCPU cores
- vCPU performance
- amount of memory
- block store volume
- etc…
What are some different EC2 instance sizes/types?
Just to name a few:
- t4g.nano, t4g.micro, t4g.small, t4g.medium, t4g.large, t4g.xlarge, t4g.2xlarge
- t3.nano, … t3.2xlarge
- m6g.large, … m6g.48xlarge
- a1.medium, … a1.4xlarge, a1.metal
Once you create an EC2, how do you connect to it?
The EC2 instance can be accessed via ssh using the public DNS and the private key (.pem file) given upon creation
What are Security Groups?
Security Groups acts as a firewall controlling the incoming and outgoing traffic to each EC2 instance
When defining a rule for a security group, what 3 things do you need to specify?
1) source IP addresses
2) protocol
3) port range
What’s the difference between scalability, elasticity, and resiliency?
Elasticity = a system’s ability to dynamically allocate and deallocate to resources to match the demand for its service
Scalability = a system’s capacity for increasing workload to meet peak demands without decreasing performance under its current infrastructure
Resiliency = a system’s ability to recover from failures, be it from increased workload or malicious attacks
What are the ways of paying for EC2?
- client’s account will automatically be charged for EC2 usage
- may be based on uptime, number of instances, EBS volume, and configuration of each instance
What’s an RDS?
Relation Database Service
- provides a way for clients to run and scale a relational database on the cloud
- provides database management services such as automatic backups, failure detection and recovery, and methods for controlling user permissions
Which database vendors are supported by RDS?
- Amazon Aurora
- PostgreSQL
- MySQL
- MariaSQL
- Oracle Database
- SQL Server
