Amazon Elastic File System (EFS) is a fully managed, scalable, and elastic cloud-native Network File System (NFS) that enables you to create and configure shared file systems for AWS Cloud services and on-premises resources. For Solutions Architects focused on workload migration and modernization, …Amazon Elastic File System (EFS) is a fully managed, scalable, and elastic cloud-native Network File System (NFS) that enables you to create and configure shared file systems for AWS Cloud services and on-premises resources. For Solutions Architects focused on workload migration and modernization, EFS serves as a critical component for transitioning legacy applications that depend on shared file storage.
Key features relevant to migration include:
**Scalability**: EFS automatically scales from gigabytes to petabytes of storage capacity as you add or remove files, eliminating the need to provision storage in advance. This elastic nature makes it ideal for unpredictable workloads during migration phases.
**Storage Classes**: EFS offers multiple storage classes including Standard, Infrequent Access (IA), and Archive tiers. Lifecycle management policies can automatically move files between tiers, optimizing costs during and after migration.
**Performance Modes**: Choose between General Purpose for latency-sensitive workloads and Max I/O for highly parallelized applications. Throughput modes include Bursting, Provisioned, and Elastic to match your performance requirements.
**Migration Tools**: AWS DataSync integrates seamlessly with EFS for rapid data transfer from on-premises NFS servers. This accelerates migration timelines significantly compared to manual transfer methods.
**Multi-AZ Availability**: EFS stores data redundantly across multiple Availability Zones, providing high durability and availability essential for business-critical applications.
**Integration Capabilities**: EFS integrates with Amazon EC2, ECS, EKS, Lambda, and AWS Fargate, supporting containerized and serverless modernization strategies. It also supports AWS Backup for centralized backup management.
**Cross-Region Replication**: EFS Replication enables automatic, transparent replication to another AWS Region for disaster recovery and compliance requirements.
When modernizing workloads, EFS provides a familiar POSIX-compliant file system interface, reducing application refactoring efforts while enabling cloud-native benefits like elasticity and managed infrastructure.
Amazon EFS: Complete Guide for AWS Solutions Architect Professional
Why Amazon EFS is Important
Amazon Elastic File System (EFS) is a critical service for the AWS Solutions Architect Professional exam because it addresses a fundamental challenge in cloud architecture: providing shared, scalable file storage across multiple compute instances. Understanding EFS is essential for designing highly available, scalable applications that require concurrent access to file data from multiple sources.
What is Amazon EFS?
Amazon EFS is a fully managed, elastic, serverless file storage service that provides a simple, scalable, and persistent file system for use with AWS Cloud services and on-premises resources. It uses the Network File System version 4 (NFSv4) protocol and can be mounted on multiple EC2 instances simultaneously.
Key Characteristics: - Elastic scaling: Automatically grows and shrinks as you add and remove files - Shared access: Thousands of EC2 instances can access an EFS file system concurrently - Regional service: Data is stored across multiple Availability Zones for high availability - POSIX-compliant: Supports standard file system semantics - Serverless: No infrastructure to manage
How Amazon EFS Works
Architecture Components:
1. File System: The primary resource where data is stored 2. Mount Targets: Network endpoints in each Availability Zone that EC2 instances use to mount the file system 3. Access Points: Application-specific entry points that enforce user identity and root directory
Storage Classes: - Standard: For frequently accessed files, stored across multiple AZs - Standard-Infrequent Access (Standard-IA): Lower cost for less frequently accessed data - One Zone: Single AZ storage at reduced cost - One Zone-IA: Single AZ with infrequent access pricing
Performance Modes: - General Purpose: Ideal for latency-sensitive use cases (default) - Max I/O: Higher levels of aggregate throughput and operations per second
Throughput Modes: - Bursting: Throughput scales with file system size - Provisioned: Specify throughput independent of storage size - Elastic: Automatically scales throughput up or down based on workload
Common Use Cases
- Content management and web serving - Big data analytics - Media processing workflows - Container storage (ECS, EKS, Fargate) - Machine learning training data - Home directories - Application development and testing
Security Features
- Encryption at rest: Using AWS KMS keys - Encryption in transit: Using TLS - VPC security groups: Control network access to mount targets - IAM policies: Control API access - EFS Access Points: Enforce application-specific permissions - POSIX permissions: Standard Linux file-level permissions
Lifecycle Management
EFS Lifecycle Management automatically moves files between storage classes based on access patterns. You can configure policies to transition files to IA storage after 7, 14, 30, 60, or 90 days of no access.
EFS vs Other Storage Options
EFS vs EBS: - EFS is shared storage accessible by multiple instances; EBS is block storage attached to a single instance - EFS scales automatically; EBS requires manual provisioning - EFS is regional; EBS is AZ-specific
EFS vs S3: - EFS is a file system with POSIX compliance; S3 is object storage - EFS is mountable; S3 requires API calls or third-party tools - EFS has lower latency for file operations
EFS vs FSx: - EFS uses NFS protocol; FSx offers Windows (SMB) and Lustre options - Choose FSx for Windows when you need Windows-native features - Choose FSx for Lustre for high-performance computing workloads
Exam Tips: Answering Questions on Amazon EFS
1. Recognize EFS Scenarios: Look for keywords like shared file storage, NFS, multiple EC2 instances accessing same data, Linux workloads, and persistent storage for containers.
2. Performance Mode Selection: - Choose General Purpose when latency is the primary concern - Choose Max I/O when you need highest possible throughput with many concurrent clients
3. Throughput Mode Selection: - Bursting: When your workload is spiky and correlates with data size - Provisioned: When you need consistent high throughput with small data sets - Elastic: When workloads are unpredictable and you want automatic scaling
4. Cost Optimization Questions: - Enable Lifecycle Management to move infrequently accessed files to IA storage - Consider One Zone storage classes for development environments or reproducible data - Use Intelligent-Tiering when access patterns are unknown
5. High Availability Requirements: - Standard storage classes replicate data across multiple AZs by default - One Zone storage classes do not provide multi-AZ resilience - Create mount targets in each AZ where your instances reside
6. Security Questions: - Remember that encryption at rest must be enabled at file system creation - Access Points can enforce user identity and subdirectory access - Security groups control network-level access to mount targets
7. Container and Serverless Integration: - EFS works with ECS, EKS, and Fargate for persistent container storage - Lambda functions can access EFS when configured with VPC access
8. Hybrid and Multi-Region Scenarios: - AWS DataSync can replicate data between on-premises and EFS - EFS Replication can copy data between regions for disaster recovery - Use AWS VPN or Direct Connect for on-premises access to EFS
9. Common Exam Traps: - EFS only supports Linux-based instances (not Windows) - EFS is regional, not global - Mount targets are required in each AZ you want to access EFS from - EBS Multi-Attach is not a replacement for EFS shared storage semantics
10. When NOT to Choose EFS: - Windows workloads requiring SMB protocol (use FSx for Windows) - High-performance computing requiring sub-millisecond latency (consider FSx for Lustre) - Object storage needs (use S3) - Single instance block storage (use EBS)