Overall AWS Flashcards
Full review
What is the proper way to use IAM for users and security for daily activities.
The initial registering user is the root user. They have full unrestricted access and should not be used for day to day activities. Instead create a IAM group (security group) and add IAM users to that group. Those users are used for daily activities.
Difference between a Region and a Availability Zone
Region are set areas around the world that have access. Availability zones are connected areas that comprise a region.
Benefit of having many regions/AZs
Lower Latency (faster access)
Global Footprint/presence
Adhere to govenment regulations (run commands in different region)
High availability (good for crash situations)
AZs have redundant power, why?
If something goes down/a crash, can utilize extra power
Simple summary of the EC2 service?
Essentially just rentable virtual servers (instances) where you can run software, commands, etc.
What is EC2 AMI
Template for what operating system and software needed for the instance.
What is important about the EC2 instance type
Instance type decided hardware configuration. Think CPU, GPU, memory, etc.
What is an instance family
Specialized hardware configuration. Some instance families have higher GPU, or higher CPU, or are balanced depending on the use case.
Describe how Key Pairs work in security
Key pairs are composed of public and private keys. Public keys are stored on the EC2 instance while private keys are stored by the user (its typically just a file). Both are necessary to access the instance.
What are security groups
A virtual firewall to control incoming and outgoing traffic to/from AWS resources.
Default is deny
Only allow rules
Describe the monitoring tab (EC2)
Holds metrics related to the instance. Cloud Watch is the monitoring service that powers these metrics
Why are elastic IP addresses important.
Stopping an instance will remove the public IP address and generate a new one when starting again. Elastic IP addresses allows an instance to keep the same public IP address.
Are IP addresses free as long as they are attached to an instance?
NOT ANYMORE. They used to be free if attached.
Difference between IaaS and PaaS
IaaS (infrastructure as a Service): Using only infrastructure from cloud provider. Customer responsible for OS upgrades and patches, app code and runtime, availability, scalability, load balancing, etc. (Think EC2)
PaaS (Platform as a Service): More is handled by the Cloud provider. Customer only responsible for App code/configuration. (think Beanstalk)
Would Elastic Load Balancing better fit under PaaS or IaaS
PaaS. AWS makes sure patches are up to date and takes care of auto scaling. More specifically, it is a managed service.
What is the Elastic Load Balancer (ELB)
Distributes traffic across EC2 instances in one or more AZs in a SINGLE region (IE region specific)
What is a Classic ELB type
Supports Layer 4 (TCP/TLS) and Layer 7 (HTTP/HTTPS) protocols. NOT RECOMMENDED BY AWS
What is an Application ELB type
Supports HTTP/HTTPs protocols. Most popular ELB. Support advanced routing approaches (based on different parts of access request)
What is a Network ELB type
Supports TCP/TLS protocols. Specifically used for High performance needs.
What is a Gateway ELB type
Distributes traffic across multiple virtual Third party appliances based on demand.
In EC2, describe how to achieve higher availability.
Deploy to multiple AZs in multiple regions. Load balancer between those.
Describe vertical vs horizontal scaling (scalability). Which is preferred?
Vertical scaling mean increasing instance size (T2.nano –> T2.Large)
Horizontal scaling increases number of instances (requires auto scale group and load balancer tho)
Horizontal scaling is typically better since it is usually less expensive and increases availability.
