ec2.txt

EC2 - web service that provides resizable compute capacity in the cloud

On Demand
- for users that want low cost and flexibility
- applications with short term, spiky, unpredictable workloads
- initial testing on EC2

Reserved Instances
- apps with steady or predictable usage
- applications that require reserved capacity
- users can make up-front payments to reduce total cost
- Standard Reserved Instance
--- up to 75% off on-demand cost
- Convertible Reserved Instance
--- up to 54% off on-demand cost
--- capability to change attributes of Reserved Instance as long as exchange results in creation of Reserved Instances of equal or greater value
- Scheduled Reserved Instance
--- available to launch within time window you reserved
--- allows you to match capacity reservation to a predictable, recurring schedule

Spot Instances
- flexible start and end times
- only feasible at very low compute prices
- users with urgent need for large amounts of additional computing capacity

Dedicated Hosts
- useful for regulatory requirements that may not support multi-tenant virtualization
- useful for licensing that doesn't support cloud deployments
- can be purchased on-demand
- can be purchased as reservation for up to 70% off on-demand price

Instance Types
F - FPGA (Field Programmable Gate Array)
I - IOPS
G - Graphics
H - High Disk Throughput
T - cheap general purpose (think T2 micro)
D - Density
R - RAM
M - Main choice for general purpose apps
C - Compute
P - Graphics (think Pics)
X - Extreme Memory

EBS - Elastic Block Storage
- Attach block storage to EC2 instances
- placed in a specific AZ, automatically replicated to protect you from single-component failure
- if windows/linux installed on disk, it's called the "root device volume"
- Can't mount 1 EBS volume on multiple EC2 instances. Use EFS instead

EBS Volume Types
- General Purpose SSD (GP2)
--- General purpose, price/performance balance
--- 3 IOPS/GB up to 10,000 IOPS and bursts up to 3,000 IOPS for extended periods for volumes 3334GB+
--- Less than 500 MiB/s
- Provisioned IOPS SDD (IO1)
--- Designed for IO intensive applications or NoSQL databases
--- Used when needing more than 10,000 IOPS
--- Can provision up to 20,000 IOPS/Volume
--- More than 500 MiB/s
- Throughput Optimized HDD (ST1)
--- Big Data
--- Data warehouses
--- Log processing
--- Cannot be boot volume
- Cold HDD (SC1)
--- Lowest cost storage, infrequently accessed
--- Typically a file server
- Magnetic (Standard)
--- Lowest cost per gigabyte of all volume times that are bootable
--- start dev here and move up when you're ready


Instance Metadata
- http://169.254.169.254/latest/meta-data/

Status Checks:
- System Status Checks: underlying layer (TCP, etc, to see if the instances recieves network packages)
- Instance Status Checks: software and network

Termination protection is OFF by default