AWS(part-3)

AWS TAGS 

A tag is a label that you assign to an AWS resource.  

Each tag consists of a key and an optional value, both of which you define.

Let’s understand this with a simple use-case:

There are three EC2 instances running. How will you identify them?

A resource can have multiple tags assigned to it.

Important Pointers for Tags:

AWS has hundreds of services. Not all of them support tagging.

Maximum number of tags per resource – 50

Tag keys and values are case-sensitive.

Important Use-Cases for Tags - Billing

Tags can be integrated into Billing and that allows customers to understand their AWS bill in a granular way. 

Important Use-Cases for Tags - IAM

Tags can be used with IAM to control access to resources. Example Use-case: Allow Alice to only delete resources which has a tag of env as development.

Follow the Tagging Strategy

It is important to have a consistent and effective tagging strategy.

Example 

Alice creates a resource with the tag of the key of env and value of production

Matthew creates a resource with the tag of Env and value of Production

Follow the AWS Tagging Strategies document.

Auto-Scaling

Overview of Scalability

Scalability is the ability of a system to change in size depending on the needs.

Infrastructure should scale to support changes in traffic patterns.

Real World Use-Case:

• During college times, I used to have a blog for KPLABS.

• Traffic used to be quiet high during night times when compared today.

• I had to launch a high configuration server to support nighttime traffic.

• The server resource remained unused during the day-time.

Better Way - Auto-Scaling

What if new servers automatically get launched on high load?

Simple Scaling Policy:

Base instance level:  2 servers 

Scalable :

    If average CPU utilization > 70%      ;     add two more instance

          If average CPU utilization < 25%       ;     remove two more instance

Overview of Auto-Scaling

AWS Auto-Scaling monitors the applications and automatically adjusts the capacity of servers.

Auto-Scaling is not just associated with servers, but can also be used with Amazon DynamoDB, Aurora, ECS and others.

Simple Storage Service (S3)

AWS S3  is object storage designed to store and retrieve any amount of data from anywhere 

It is designed for 99.999999999% durability and 99.99% availability.

The thing that makes AWS S3 so powerful are the features that it comes preloaded with which are simply the best.

Let’s understand this with a use-case:

Large Corp is a payments organization and has more than 1000 servers. As being PCI DSS compliant, they must retain their logs for 1 year. It has been found that every day, the payment server generates logs of 200 GB.  How to achieve this use case pertaining to the storage capacity in a cost-effective manner?

S3 Terminology

There are two important terminologies in AWS S3 :

• Buckets 

• Objects

Buckets are like “Folders” where you can store multiple files (objects)

S3 Storage Classes

S3 offers various kinds of storage classes for different use cases:-

• Standard

• Intelligent-Tiering

• Standard-IA

• One Zone-IA

• Glacier

• Glacier Deep Archive

• Reduced Redundancy

Durability vs Availability

Durability is percent ( % ) over one year period of time that the file which is stored in S3

          will not be lost.

Availability is percent (%) over one year period of time that the file stored in S3 will 

           not be available.

Example:-

        For Servers, Availability is one of the key metrics and any minute of downtime is a loss.

        However, what happens if the component of the server itself fails and the server goes down? 

Understanding Every S3 Storage Class

S3 Standard:

Amazon S3 Standard offers high durability, availability and performance for objects stored.

Designed for durability of 99.999999999% of objects ( eleven nines )

Designed for 99.99% availability over a given year

Example:-

  

If we have 10,000 files stored in S3 ( 11 nines durability ) then you can expect to lose one file every ten million years.

S3 Standard In-Frequent Access:

Amazon S3 Standard - Infrequent Access is for data that is accessed less frequently but requires rapid access when needed.

Designed for durability of 99.999999999% of objects

Designed for 99.90% availability over a given year

S3 Reduced Redundancy Storage (RRS)

AWS S3 Reduced Redundancy storage enables customers to reduce their costs by storing non-critical, reproducible data at lower levels of redundancy than Amazon S3’s standard storage

Designed for durability of 99.99% of objects

Designed for 99.99% availability over a given year

Glacier

• AWS Glacier is meant to be for archiving and for storing long-term backups.

• It may take several hours for the object to get restored.

• 
  

• 99.999999999% durability of object.

• It is much cheaper than S3 ( very low cost )

Example Use Case:-

Backup of Application logs more than 1 year older can be moved to Glacier.

AWS S3 Intelligent Tiering

The S3 Intelligent Tiering is primarily designed to optimize cost by automatically moving data to the most cost-effective tier.

General Purpose   -     Standard S3

Infrequent Access -    Standard IA

1TB of data stored in Standard S3  = 22.88$

1TB of data stored in Standard IA  = 12.50$

Organization stores terabytes of data in S3.

It will be great if a solution automatically moves infrequent data to Standard IA.

The S3 Intelligent Tiering works by storing data in one of the two access tiers:

• Frequent Access Tier     (Costly)

• Infrequent Access Tier  (Much cheaper)

In this tier, the objects are automatically moved to frequent or infrequent access tier based on the access patterns.

Amazon S3 monitors access patterns of the objects in S3 Intelligent-Tiering and moves the ones that have not been accessed for 30 consecutive days to the infrequent access tier.

If an object in the infrequent access tier is accessed, it is automatically moved back to the frequent access tier.

This type of storage class is preferable for long-lived data with access patterns that are unknown or unpredictable.

S3 Intelligent-Tiering like other storage classes is configured at the object level.

1TB of data stored in Standard S3  = 22.88$

1TB of data stored in Standard IA  = 12.50$

1 TB of data stored with Standard-Intelligent = 23$

One Zone Infrequent Access (One Zone IA)

Storage classes like Standard S3, Standard IA stores the data in minimum of 3 availability zones.

Due to this, the overall cost per of storage is increased with such architecture. 

S3 One Zone-IA stores data in a single AZ and costs 20% less than S3 Standard-IA.

It’s a good choice for storing secondary backup copies of on-premises data or easily recreatable data.

Data will be lost in-case of availability zone destruction.

Overview of Pricing comparison between storage classes:

• 1TB of data stored in Standard S3  = 22.88$

• 1TB of data stored in Standard IA  = 12.50$

• 1 TB of data stored in One Zone IA = 10$

Glacier Deep Archive

S3 Glacier Deep Archive is Amazon S3’s lowest-cost storage class and supports long-term retention and digital preservation for data that may be accessed once or twice in a year.

All data stored in S3 Glacier Deep Archive can be restored within 12 hours.

On the contrary, Glacier is ideal for archives where data is regularly retrieved and some of the data may be needed in minutes.

Pricing Comparison:

1 TB of data stored in Glacier: 14$

1 TB of data stored in Glacier Deep Archive:  10.99$