Files
AWS-CCP-Notes/ec2.md

253 lines
10 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
# EC2: Virtual Machines
## What is Amazon EC2?
Amazon Elastic Compute Cloud (Amazon EC2) provides scalable computing capacity in the Amazon Web Services (AWS) Cloud.
* EC2 is one of the most popular of AWS offering
* EC2 = Elastic Compute Cloud = Infrastructure as a Service
* It mainly consists in the capability of :
* Renting virtual machines (EC2)
* Storing data on virtual drives (EBS)
* Distributing load across machines (ELB)
* Scaling the services using an auto-scaling group (ASG)
* Knowing EC2 is fundamental to understand how the Cloud works
## EC2 sizing & configuration options
* Operating System (OS): Linux, Windows or Mac OS
* How much compute power & cores (CPU)
* How much random-access memory (RAM)
* How much storage space:
* Network-attached (EBS & EFS)
* hardware (EC2 Instance Store)
* Network card: speed of the card, Public IP address
* Firewall rules: **security group**
* Bootstrap script (configure at first launch): EC2 User Data
## EC2 User Data
* It is possible to bootstrap our instances using an **EC2 User data** script.
* **bootstrapping** means launching commands when a machine starts
* That script is **only run once** at the instance **first start**
* EC2 user data is used to automate boot tasks such as:
* Installing updates
* Installing software
* Downloading common files from the internet
* Anything you can think of
* The EC2 User Data Script runs with the root user
## EC2 Instance Types - Overview
* You can use different types of EC2 instances that are optimised for different use cases (<https://aws.amazon.com/ec2/instance-types/>)
* [General Purpose](#general-purpose)
* [Compute Optimized](#compute-optimized)
* [Memory Optimized](#memory-optimized)
* [Storage Optimized](#storage-optimized)
* Accelerated Computing
* AWS has the following naming convention: m5.2xlarge
* m: instance class
* 5: generation (AWS improves them over time)
* 2xlarge: size within the instance class
## General Purpose
* Great for a diversity of workloads such as web servers or code repositories
* Balance between:
* Compute
* Memory
* Networking
## Compute Optimized
* Great for compute-intensive tasks that require high performance processors:
* Batch processing workloads
* Media transcoding
* High performance web servers
* High performance computing (HPC)
* Scientific modeling & machine learning
* Dedicated gaming servers
## Memory Optimized
* Fast performance for workloads that process large data sets in memory
* Use cases:
* High performance, relational/non-relational databases
* Distributed web scale cache stores
* In-memory databases optimized for BI (business intelligence)
* Applications performing real-time processing of big unstructured data
## Storage Optimized
* Great for storage-intensive tasks that require high, sequential read and write access to large data sets on local storage
* Use cases:
* High frequency online transaction processing (OLTP) systems
* Relational & NoSQL databases
* Cache for in-memory databases (for example, Redis)
* Data warehousing applications
* Distributed file systems
## Introduction to Security Groups
* Security Groups are the fundamental of network security in AWS
* They control how traffic is allowed into or out of our EC2 Instances.
* Security groups only contain allow rules
* Security groups rules can reference by IP or by security group
## Deeper Dive
* Security groups are acting as a “firewall” on EC2 instances
* They regulate:
* Access to Ports
* Authorised IP ranges IPv4 and IPv6
* Control of inbound network (from other to the instance)
* Control of outbound network (from the instance to other)
## The fundamental of network security in AWS (Good to know)
* Can be attached to multiple instances
* Locked down to a region / VPC combination
* Does live “outside” the EC2 if traffic is blocked the EC2 instance wont see it
* Its good to maintain one separate security group for SSH access
* If your application is not accessible (time out), then its a security group issue
* If your application gives a “connection refused“ error, then its an application error or its not launched
* All inbound traffic is blocked by default
* All outbound traffic is authorised by default
## Classic Ports to know
* 22 = SSH (Secure Shell) - log into a Linux instance
* 21 = FTP (File Transfer Protocol) upload files into a file share
* 22 = SFTP (Secure File Transfer Protocol) upload files using SSH
* 80 = HTTP access unsecured websites
* 443 = HTTPS access secured websites
* 3389 = RDP (Remote Desktop Protocol) log into a Windows instance
## EC2 Instance Launch Types
* [**On Demand Instances**](#on-demand-instance): short workload, predictable pricing
* [**Reserved**](#reserved-instances): (1 & 3 years)
* **Reserved Instances**: long workloads
* **Convertible Reserved Instances**: long workloads with flexible instances
* [**Savings Plans**](#savings-plans) (1 & 3 years): commitment to an amount of usage, long workload
* [**Spot Instances**](#spot-instances): short workloads, for cheap, can lose instances
* [**Dedicated Instances**](#dedicated-instances): no other customers will share your hardware
* [**Dedicated Hosts**](#dedicated-hosts): book an entire physical server, control instance placement
* [**Capacity Reservations**](#capacity-reservations): reserve capacity in a specific AZ for any duration
### On Demand Instance
* Pay for what you use:
* Linux or Windows - billing per second, after the first minute
* All other operating systems - billing per hour
* Has the highest cost but no upfront payment
* No long-term commitment
* Recommended for **short-term** and **un-interrupted workloads**, where you can't predict how the application will behave
### Reserved Instances
* Up to 72% discount compared to On-demand
* You reserve a specific instance attributes (Instance Type, Region, Tenancy, OS)
* Reservation Period 1 year (+discount) or 3 years (+++discount)
* Payment Options No Upfront (+), Partial Upfront (++), All Upfront (+++)
* Reserved Instances Scope Regional or Zonal (reserve capacity in an AZ)
* Recommended for steady-state usage applications (think database)
* You can buy and sell in the Reserved Instance Marketplace
* Convertible Reserved Instance
* Can change the EC2 instance type, instance family, OS, scope and tenancy
* Up to 66% discount
### Savings Plans
* Get a discount based on long-term usage (up to 72% - same as RIs)
* Commit to a certain type of usage ($10/hour for 1 or 3 years)
* Usage beyond EC2 Savings Plans is billed at the On-Demand price
* Locked to a specific instance family & AWS region (e.g., M5 in us-east-1)
* Flexible across:
* Instance Size (e.g., m5.xlarge, m5.2xlarge)
* OS (e.g., Linux, Windows)
* Tenancy (Host, Dedicated, Default)
### Spot Instances
* Can get a discount of up to 90% compared to On-demand
* Instances that you can “lose” at any point of time if your max price is less than the current spot price
* The MOST cost-efficient instances in AWS
* Useful for workloads that are resilient to failure
* Batch jobs
* Data analysis
* Image processing
* Any distributed workloads
* Workloads with a flexible start and end time
* Not suitable for critical jobs or databases
### Dedicated Hosts
* A physical server with EC2 instance capacity fully dedicated to your use
* Allows you address compliance requirements and use your existing server- bound software licenses (per-socket, per-core, pe—VM software licenses)
* Purchasing Options:
* On-demand pay per second for active Dedicated Host
* Reserved - 1 or 3 years (No Upfront, Partial Upfront, All Upfront)
* The most expensive option
* Useful for software that have complicated licensing model (BYOL Bring Your Own License)
* Or for companies that have strong regulatory or compliance needs
### Dedicated Instances
* Instances run on hardware thats dedicated to you
* May share hardware with other instances in same account
* No control over instance placement (can move hardware after Stop / Start)
### Capacity Reservations
* Reserve On-Demand instances capacity in a specific AZ for any duration
* You always have access to EC2 capacity when you need it
* No time commitment (create/cancel anytime), no billing discounts
* Combine with Regional Reserved Instances and Savings Plans to benefit from billing discounts
* Youre charged at On-Demand rate whether you run instances or not
* Suitable for short-term, uninterrupted workloads that needs to be in a specific AZ
## Which purchasing option is right for me?
* On demand: coming and staying in resort whenever we like, we pay the full price
* Reserved: like planning ahead and if we plan to stay for a long time, we may get a good discount.
* Savings Plans: pay a certain amount per hour for certain period and stay in any room type (e.g., King, Suite, Sea View, …)
* Spot instances: the hotel allows people to bid for the empty rooms and the highest bidder keeps the rooms. You can get kicked out at any time
* Dedicated Hosts: We book an entire building of the resort
* Capacity Reservations: you book a room for a period with full price even you dont stay in it
## Price Comparison Example m4.large us-east-1
Price Type | Price (per hour)
------------ | ------------
On-Demand | $0.10
Spot Instance (Spot Price) | $0.038 - $0.039 (up to 61% off)
Reserved Instance (1 year) | $0.062 (No Upfront) - $0.058 (All Upfront)
Reserved Instance (3 years) | $0.043 (No Upfront) - $0.037 (All Upfront)
EC2 Savings Plan (1 year) | $0.062 (No Upfront) - $0.058 (All Upfront)
Reserved Convertible Instance (1 year) | $0.071 (No Upfront) - $0.066 (All Upfront)
Dedicated Host | On-Demand Price
Dedicated Host Reservation | Up to 70% off
Capacity Reservations | On-Demand Price
## Shared Responsibility Model for EC2
AWS | USER
------- | -------
Infrastructure (global network security) | Security Groups rules
Isolation on physical hosts | Operating-system patches and updates
Replacing faulty hardware | Software and utilities installed on the EC2 instance
Compliance validation | IAM Roles assigned to EC2 & IAM user access management, Data security on your instance
## EC2 Section Summary
* EC2 Instance: AMI (OS) + Instance Size (CPU + RAM) + Storage + security groups + EC2 User Data
* Security Groups: Firewall attached to the EC2 instance
* EC2 User Data: Script launched at the first start of an instance
* SSH: start a terminal into our EC2 Instances (port 22)
* EC2 Instance Role: link to IAM roles
* Purchasing Options: On-Demand, Spot, Reserved (Standard + Convertible + Scheduled), Dedicated Host, Dedicated Instance