EC2 Instance Store is a temporary block-level storage option for Amazon EC2 instances that provides high-performance local storage physically attached to the host computer. This storage is ideal for temporary data that changes frequently, such as buffers, caches, scratch data, and other temporary c…EC2 Instance Store is a temporary block-level storage option for Amazon EC2 instances that provides high-performance local storage physically attached to the host computer. This storage is ideal for temporary data that changes frequently, such as buffers, caches, scratch data, and other temporary content.
Key characteristics of EC2 Instance Store:
1. **Ephemeral Nature**: Data on instance store volumes persists only during the lifetime of the associated instance. When an instance stops, terminates, or fails, all data on the instance store is lost. This makes it unsuitable for persistent data storage.
2. **High Performance**: Instance store volumes offer very high I/O performance because they are physically attached to the host. They provide low latency and high throughput, making them excellent for applications requiring fast read/write operations.
3. **No Additional Cost**: Instance store comes included with certain EC2 instance types at no extra charge beyond the instance cost itself.
4. **Instance Type Dependent**: Not all instance types support instance store. The availability and size of instance store volumes depend on the instance type selected during launch.
5. **Use Cases**: Best suited for temporary storage needs like caching layers, temporary processing files, and data that can be easily regenerated or retrieved from other sources.
For SysOps Administrators, understanding instance store is crucial when:
- Designing backup strategies (instance store data requires separate backup mechanisms)
- Planning for high availability (data must be replicated elsewhere)
- Optimizing performance for specific workloads
- Automating deployments with CloudFormation or other IaC tools
When provisioning EC2 instances, administrators should carefully evaluate whether instance store meets their durability requirements. For persistent data, Amazon EBS volumes should be used instead, as they provide data persistence independent of instance lifecycle.
EC2 Instance Store - Complete Guide for AWS SysOps Administrator Associate
What is EC2 Instance Store?
EC2 Instance Store provides temporary block-level storage for your EC2 instances. This storage is physically attached to the host computer where your instance runs, offering extremely high I/O performance. The storage is also known as ephemeral storage because data persists only during the lifetime of the associated instance.
Why is EC2 Instance Store Important?
Understanding Instance Store is crucial for several reasons:
• Performance Requirements: Instance store volumes provide the highest possible I/O performance for workloads requiring millions of IOPS • Cost Efficiency: Instance store comes at no additional cost - it's included with supported instance types • Data Persistence Planning: Critical for designing fault-tolerant architectures since data loss occurs when instances stop or terminate • Use Case Selection: Essential for choosing the right storage solution for temporary data, buffers, caches, and scratch data
How EC2 Instance Store Works
1. Physical Attachment: Instance store volumes are physically attached to the host server as NVMe SSDs or SSD-backed storage
2. Lifecycle: Data on instance store volumes persists only while the instance is running. Data is lost when: • The underlying disk drive fails • The instance stops (not just reboots) • The instance terminates • The instance hibernates
3. Instance Types: Not all instance types support instance store. Check instance type specifications - look for instance types with 'd' in the name (e.g., m5d, c5d, i3)
4. Configuration: Instance store volumes must be specified at launch time and cannot be attached after the instance is running
5. Performance Characteristics: • Very high IOPS (millions for some instance types) • Very low latency • High throughput • Performance scales with instance size
Key Differences: Instance Store vs EBS
• Persistence: EBS persists independently; Instance Store is ephemeral • Attachment: EBS can be detached/reattached; Instance Store cannot • Snapshots: EBS supports snapshots; Instance Store does not • Encryption: Both support encryption • Performance: Instance Store typically offers higher performance for supported instance types
Common Use Cases
• Buffer and cache storage • Temporary content storage • Scratch data and temporary files • Data replicated across a fleet of instances • High-performance computing temporary storage • Big data processing with distributed storage systems
Exam Tips: Answering Questions on EC2 Instance Store
Tip 1: When a question mentions highest possible I/O performance or millions of IOPS, think Instance Store first
Tip 2: If a question asks about temporary data, caches, buffers, or scratch data that can be recreated, Instance Store is usually the answer
Tip 3: Questions about data persistence after stopping an instance - remember Instance Store data is LOST, only reboot preserves data
Tip 4: Look for the 'd' designation in instance type names (m5d, c5d, r5d, i3) which indicates Instance Store support
Tip 5: If a question requires data to survive instance termination or stopping, Instance Store is NOT the correct answer - choose EBS
Tip 6: For cost-effective high-performance temporary storage, Instance Store is optimal since there's no additional charge
Tip 7: Questions about attaching storage after launch - Instance Store must be configured at launch time; you cannot add it later
Tip 8: When designing for fault tolerance with Instance Store, the application must handle data replication across multiple instances
Tip 9: Remember that Instance Store volumes cannot be used as boot volumes for most instance types
Tip 10: For questions about backing up Instance Store data, the answer involves copying data to EBS or S3, as snapshots are not supported