Amazon EC2 Instance: Storage types

Amazon EC2 Instance:  Storage types.

EBS Volume

• EBS (Elastic Block Store) Volume is a network drive that twtech can attach to its instances while they run.

• The attachment of ebs volume to an instance, enables that instance to persist data, even after that instance is terminated.

 • twtech can only mount the ebs volume to one instance at a time. 

Tips:

EC2 instance storage types and use-cases.

Summarized at the CCP(certified cloud partitional) level:

1. Instance Store (ephemeral storage)

• Temporary, local storage physically attached to the EC2 host.
• Data is lost if the instance stops or is terminated.
• Use case: Temporary storage needs like caching or scratch data.

 2. Amazon EBS (Elastic Block Store)

• Durable, persistent storage that attaches to EC2 instances.
• Can store OS, databases, or application data.
• Data remains even after stopping or terminating the instance (if not deleted).
• Use case: Boot volumes, databases, critical app storage.

 3. Amazon EFS/NFS (Elastic File System/Network file system)

• Shared file system that can be accessed by multiple EC2 instances.
• Scales automatically as files grow.
• Use case: Shared access for web servers, CMS, or analytics pipelines.

At CCP level: 

twtech-users are expected to:  

•  Understand the difference between temporary (Instance Store) and persistent (EBS/EFS) storage.
• Know when to use block storage (EBS) vs. file storage (EFS).
• Recognize that Instance Store is not durable and is not used for critical data.

 •  know that EBS volumes are bound to a specific availability zone.

•  Thererfore, twtech EBS Volume in us-east-2a cannot be attached to us-east-1b.

 • Thererfore, twtech considers an ebs volume as a “network USB stick”.

 •  twtech can have Free tier for up to 30 GB of free EBS storage of type General Purpose (SSD) or Magnetic per month.

• EBS is a network drive (it is not a physical drive).

• The ebs volume uses the network to communicate between instances, and that accounts for the reasons behind latency.

•  twtech may detached its ebs volume from an EC2 instance and attached to another.

• twtech used snapshots to move a volume across.

• The ebs volume has a provisioned capacity of size in GBs, or IOPS.

A. GBs (Gigabytes per second)

• Meaning: A measure of data transfer speed—how fast data can be read from or written to a storage device.

• Example: If a drive has a speed of 2 GB/s, it can transfer 2 gigabytes of data every second.

• Use case: Important for tasks like copying large files, streaming high-resolution video, or loading big databases quickly.

B. IOPS (Input/Output Operations Per Second)

• Meaning: A measure of how many individual read/write operations a storage system can handle per second.

• Example: A drive with 10,000 IOPS can process 10,000 read or write commands each second.

• Use case: Crucial for workloads with lots of small, random reads/writes, like databases or high-traffic web servers.

• twtech is billed for its provisioned ebs volumes.

• twtech may decide to increase or decrease the capacity of the drive over time by scaling their volumes vertically (same volume)  or horizontally (different  volumes). 

Advance-Settings:

Delete on termination, Controls the EBS behaviour when an EC2 instance terminates,

• By default, the root EBS volume is deleted (Yes).

• By default, any other attached EBS volume is not deleted (No).

• This can be managed via AWS console and  CLI.

twtech-addendum:

Amazon EC2 – Instance Storage types and usecases

Amazon EC2 offers several instance storage types, each designed for different performance characteristics and use cases. Here's a breakdown of the main storage options and when to use them.

 1. Instance Store (Ephemeral Storage)

Key Traits:

• Physically attached to the host computer.
• High IOPS, low latency.
• Data is lost when the instance stops, hibernates, or terminates.
• Cannot be detached or moved between instances.

 Use Cases:

• Temporary data like cache, buffers, scratch data, or temporary logs.
• Applications with high-speed, short-term storage needs (e.g., video processing, batch jobs).
• High-performance NoSQL databases where persistence is handled elsewhere.

2.    Elastic Block Store (Amazon EBS)

Key Traits:

• Network-attached, persistent block storage.
• Survives instance stop/start/termination (if not explicitly deleted).
• Can be snapshotted, resized, and attached/detached from instances.
• Supports encryption and backup.

Types of EBS volumes:

Type	Key Feature	Use Case
gp3 / gp2	General Purpose SSD	Boot volumes, dev/test workloads
io2 / io1	Provisioned IOPS SSD	Databases like MySQL, PostgreSQL, Oracle
st1	Throughput Optimized HDD	Big data, data warehouses, log processing
sc1	Cold HDD	Infrequently accessed, low-cost storage

Use Cases:

• Boot volumes, application storage.
• Databases, transactional systems, persistent volumes.
• Systems that need durability and reliability.

 3. Amazon EFS (Elastic File System) – Not EC2-specific, but often used with EC2

Key Traits:

• Fully managed, elastic NFS file system.
• Accessible by multiple EC2 instances across AZs.
• Scales automatically.

Use Cases:

• Shared file storage across EC2 instances.
• CMS systems, web servers, data science pipelines.
• Applications needing a common file system.

 4. Amazon FSx – File storage optimized for specific workloads (e.g., FSx for Windows, Lustre)

 twtech-Summary Table

Storage Type	Persistent	Performance	Use Cases
Instance Store	❌ No	Very high	Cache, temp files, scratch data
EBS (gp3/io1/st1)	✅ Yes	Medium to high	Boot, databases, general workloads
EFS	✅ Yes	Shared, scalable	Shared file systems, multi-AZ access
FSx	✅ Yes	Specialized	Windows apps, HPC, Lustre file systems

How twtech configures and terminate its EC2 instance but retains the EBS root volume with its data still intact.

Step-by-Step in the AWS Console:

1. Go to the EC2 Dashboard.
2. Select the instance you want to terminate.
3. Click the "Actions" dropdown, then go to:
• Instance settings → Change Termination Protection → Make sure it's disabled (select: NO).
4. Now go to:
• Actions → Instance settings → Change root volume delete behavior.
5. Uncheck the box “Delete on termination” for the root volume (usually /dev/xvda or /dev/sda1).
• Or go to Volumes, find the root volume attached to the instance, and:
• Select it → Actions → Modify Volume Attachment → Uncheck "Delete on termination".
6. Click Save.
7. Now terminate the instance:
• Actions → Instance State → Terminate instance.

Notes:

• After termination, the root EBS volume will remain in your account, and twtech can:
• Attach it to another EC2 instance.
• Create a snapshot or AMI from it.
• Mount it as a secondary volume to inspect or recover data.

 CLI Equivalent:

twtech can also use the AWS CLI:

#   bash

aws ec2 modify-instance-attribute \

    --instance-id i-xxxxxxxxxxxxxxxxx \

    --block-device-mappings "[{\"DeviceName\":\"/dev/xvda\",\"Ebs\":{\"DeleteOnTermination\":false}}]"

Then terminate the instance:

#  bash 

aws ec2 terminate-instances --instance-ids i-xxxxxxxxxxxxxxxxx

Project:

How twtech creates an ebs volume and attach it to an instance.

Go EC2 console and navigate to elastic block store, then: volumes

us-east-2 is selected because it  corresponds to zone where the instance is located. ( same AZ)

Add tags

Create volume:

Attach volume to instance in the same AZ. Make sure the state is:  available.

Select the instance and device name to attach volume to:

Verify that the volume has been attached to the instance:

Successfully, twtech-web-server storage has been horizontally scaled (another volume added)

How twtech detaches and delete unwanted ebs volumes that is attached to an instance:

First:

Detach volume from instance

Confirm to detach:

Next. Delete the detached volume: refresh the page if need be.

Confirm and detete volume:

NB:

If twtech terminates an instance, the root volume is destroyed because by default delete on termination is set: YES.

This can also be configure to, if need be : No (root-volume will not be deleted on termination of instance)

But the created and attached ebs volume remains available.

Verify that the instance (twtech-webserver) has only the root volume still attached:

Yes,