AWS

Challenges of on-premises Data Centers:

• Scaling of infrastructure
• Time consuming
• Expensive
• Wasting resources

Cloud Service:

• Any Service which is made available to the user via Internet based on the demand.
• From a Cloud Computing provider’s Servers.
• EC2 Instance.

Cloud Computing:

• Cloud Computing is the delivery of computing Services-Servers,
• Storage
• Database
• Networking
• Software
• Analytics and more over the internet.

Cloud Service Models:

1. IaaS  (Host) -----------------------> Ec2
2. Paas  (Build) --------------------->  EKS , RDS
3. SaaS  (Consume) --------------->   Cloud Watch

Advantages of AWS:

• Cost-Effectiveness ------------ Pay as you Go
• Elasticity & Agility
• Flexibility  & Openness
• Security
• Reliable & High Performance

AWS Global Infrastructure:

• Regions -----------------22
• Availability Zones ----55

How to choose the right Region in AWS?                  (Interview Question)

• User/Customer Location
• Pricing
• Latency
• Security & Compliance Requirement
• Service Availability

Physical Machine:

Virtual Machne / Virtualization:

EC2:

• EC2 provides scalable computing capacity in the AWS cloud.
• EC2 enables you to scale up or down to handle changes in requirement.

Ec2 Types:

• On demand
• Reserved
• Spot instances

AWS Storage Services:

• Object Storage  --------------  S3 Bucket
• File Storage  ------------------  EFS
• Block Storage  ---------------- EBS

EBS :-----------  Elastic Block Storage

• Elastic Block Storage
• Each EC2 have EBS Volume as a root Volume (root file system).
• It is really fast
• It is relatively cheap.
• Capacity of EBS is -------16TB / 16000GB.
• EBS we can’t share with multiple machines (Instances).
• We can’t share EBS volume with multiple Availability zones with in the Region.
• The Server and EBS should be in same availability zone.

1. How to Create an Additional Volume ?

Create EBS Volume

Attach EBS Volume to EC2

Mount directory with EBS.

• Elastic Block Store
• Volumes
• Create Volume
• Volume type -------------(SSD Provisioned & General) 
• size
• Availability Zone

How to attach EBS to EC2 ?

• select EBS
• Action
• Attach Volume
• Instance ----------------(Select from the list)
• Device name
• For Root volume ------------/dev/sdg
• For Additional EBS ---------/dev/sdf
• go to Linux
• lsblk
• 
  
  
• Since this is Raw Storage volume (Additional EBS Volume)
• Create a file system
• sudo mkfs.ext4  /dev/xvdf
• 
  
  
• create a folder and mount the drive
• dh -h
• mkdir/ebsdemo
• sudo mount   /dev/xvdf   ebsdemo/   (unmount   /EBSVOL1)

2. How to migrate the data from one availability Zone to Another Zone?       (Interview Question)

3. How to migrate the data from one Region to Another Region?                     (Interview Question)

• With help of snapshot we can do it.
• EBS snapshots
• Snapshots is nothing but backup of EBS Volume.
• Periodically we can take a backup.
• We can’t mount snapshot directly.
• We have to create a volume from the snapshot.

• Zone to Zone
• Elastic Block Storage
• Volume
• Action
• Create Snapshot
• Create Snapshot lifecycle policy
• 
  
• Region to Region  (Snapshot)
• Snapshot
• Action
• Copy
• Destination Region

4. Can we update the EBS Volume type or Size while it’s in use?             (Interview Question)

• Yes
• We can change the type and increase the volume Size.
• But we can’t decrease the size  (From 10 GB  to  5 GB)

5. If you lost your private key (.pem key) how will you recovery?            (Interview Question)

• Where the Pem key information saved
• .ssh/authorized_keys
• We have to create a new EC2 in same availability zone, with new keypair.

EFS:  ------------- Elastic File System

• EFS Native from NFS Implementation.
• No need to manage NFS , AWS will manage NFS
• Share file system
• EFS is region level service.
• Within the region irrespective of Availability Zone we can share Files.
• Automatically it will increase the size of volume and deciares the size.
• There is no limitation for store the data.
• It will charged per GB.

How create a EFS?

• Services
• EFS
• Create File system
• Name
• Choose VPC
• Mount to the instances (servers)
• go to EFS
• Select EFS from the list
• view detais
• Attach
• You need to install client software ---------EFS Client or NFS Client
• go to Linux machine
• yum install nfs-utils –y ------------(Client Software)
• apt install nfs-common -y --------(Client Software)
• mkdir DemoEFS
• sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport fs-0d9dcaa49e2b2e1c5.efs.ap-south-1.amazonaws.com:/ DemoEFS
• go to EFS (AWS)
• Copy command and past in Linux
• df -kh
• 
• Need to open port number (NFS Port - 2049)
• .
• If you want to share some static file over the same availability zone.
• We can share files, images etc.,
• If multiple servers should have access to the same content, then we can go for EFS.
• go to another server (EC2)
• Where you want to mount EFS.
• go to linux
• create a directory 
• mkdir -----------------(efs_Testing)
• go to aws
• EFS
• sudo mount -t nfs4 -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport fs-0d9dcaa49e2b2e1c5.efs.ap-south-1.amazonaws.com:/ efs_Testing

S3 Bucket:

• Object storage.
• Scalable storage in the cloud.
• S3 Bucket will access from the any region. 
• But S3 Bucket storage will maintain in some Region.
• Each object we will have a unique end point.
• Other Aws accounts also can able to manage S3 bucket, using ACL (Access Control List).
• No need to Mount.
• Create S3 Bucket
• Bucket name (Unique name)
• Region

Without mounting how can we upload the data in S3 Bucket?

• GUI ----------- Graphical User Interface
• CLI -------------Command Line Interface
• API ------------Application programing interface
• SDK ------------Software Development Kit (Boto/Boto3, Python SDK for AWS )
• IaaS Code -----(Terraform)      
• By default S3 object not able to access to the public.
• If you want to give the access to public.
• First you must give the Bucket lever access and after that object level permission to give the public access.

Bucket Policies:

we can grant permissions to specific Applications (or)  specific IP address / range using bucket policies.

ACL:

Access Control List.

We can given  permissions to S3 bucket to another AWS Accounts.

ARN:

Amazon Resource Name.

Each AWS Resource will unique ARN.

ARN is used to identify AWS resources uniquely.

 

arn:aws:<Service_Name>: <Region_Name>: <Availability_Zone>: <Resource_Name/id>

Versioning in S3:

• If i want to maintain all the versions of my object in S3 bucket.
• By default S3 bucket will not maintain the versionig.
• S3 bucket
• Properties
• Bucket Versioning
• Enable ----------------- (By default Disable)

Storage Calsses in S3:

         Charges is based on object Size & Storage class       

    1.Standard
    2.IA

    3.RRS
    4.Glacier

• Standard:
• Standard storage class is by default.
• The files which we are accessing frequiently we can maintain in standard storage calss.
• So that out object is highly available and fast retrival.
• IA:
• Infrequent Access.
• We can maintain files which we are not accessing freqently in IA.
• RRS:  One Zone-IA
• Reduced Redundency Storage.
• Not critical & Re_Producatable data we can maintain in RSS.
• Data will be maintained only in one zone (Only one copy).
• Glacier:
• We can maintain long term & archirved data in glacier for very less price.
• But charges are applicable when you read the data.
• It takes more time if you want retreive.

Object Lifecycle:

• S3 Bucket
• Lifecycle rules
• Create Lifecycle rules
• Name
• Choose a rule scope
• filter type
• prefix
• Object tags

Replication:

• we can replication S3 bucket using replication rule.
• 
  
• Same Resion Replication
• Cross Resion Replication
• .
• Versioning should be enable if you want to replication.

• S3 Bucket
• Management
• Replication rules
•  Creat Replication rules
• Name
• Choose a rule scope
• Destination

1.What is the file (object ) limit in S3?

        5000 GB / 5 TB

2. What is use case for S3?

        Best places to maintain application logs.

        Best places to maintain your application images/documents/videos (Static Content).

3. What is Snow Ball?

        It's not a service, it's kind of a request.

        It's physical data transport solution.

        If you want to tranport huge data from cloud to on-premise (or) on-premise to cloud.