EC2 instance types are fundamental to AWS infrastructure and critical for SysOps Administrators to understand. Amazon EC2 offers various instance families optimized for different workloads, each with specific combinations of CPU, memory, storage, and networking capacity.
**General Purpose (T, M se…EC2 instance types are fundamental to AWS infrastructure and critical for SysOps Administrators to understand. Amazon EC2 offers various instance families optimized for different workloads, each with specific combinations of CPU, memory, storage, and networking capacity.
**General Purpose (T, M series):** These instances provide balanced compute, memory, and networking resources. T3 and T3a instances offer burstable performance, ideal for variable workloads like web servers and development environments. M5 and M6i instances deliver consistent performance for diverse applications.
**Compute Optimized (C series):** C5 and C6i instances excel at compute-intensive tasks such as batch processing, scientific modeling, gaming servers, and high-performance computing requiring powerful processors.
**Memory Optimized (R, X, Z series):** These instances suit memory-intensive applications like in-memory databases, real-time big data analytics, and high-performance databases. R5 instances offer excellent memory-to-CPU ratios.
**Storage Optimized (I, D, H series):** Designed for workloads requiring high sequential read/write access to large datasets. I3 instances provide NVMe SSD storage for data warehousing and distributed file systems.
**Accelerated Computing (P, G, Inf series):** These leverage hardware accelerators (GPUs, FPGAs) for machine learning, graphics rendering, and floating-point calculations.
**For SysOps Automation:**
- Use AWS Systems Manager to manage instance configurations across fleets
- Implement Auto Scaling groups with appropriate instance types based on workload requirements
- Leverage Launch Templates to standardize instance deployments
- Monitor instance performance using CloudWatch metrics to right-size instances
- Use AWS Compute Optimizer for instance type recommendations
**Provisioning Considerations:**
- Consider On-Demand, Reserved, Spot, and Savings Plans pricing models
- Implement placement groups for network performance requirements
- Use instance store versus EBS based on persistence needs
Understanding instance types enables cost optimization and performance tuning, essential skills for the SysOps Administrator certification.
Understanding EC2 instance types is fundamental for any AWS SysOps Administrator because selecting the right instance type directly impacts application performance, cost optimization, and resource efficiency. In production environments, choosing an inappropriate instance type can lead to over-provisioning (wasting money) or under-provisioning (poor performance). The exam heavily tests your ability to match workload requirements with the correct instance family.
What Are EC2 Instance Types?
EC2 instance types are predefined configurations of CPU, memory, storage, and networking capacity. AWS organizes them into families based on their optimized use cases:
General Purpose (T, M series) - T3, T3a, T2: Burstable performance, ideal for variable workloads - M5, M6i, M6a: Balanced compute, memory, and networking for diverse workloads
Compute Optimized (C series) - C5, C6i, C6a: High-performance processors for compute-intensive tasks like batch processing, gaming servers, and scientific modeling
Memory Optimized (R, X, z series) - R5, R6i: High memory-to-CPU ratio for in-memory databases - X1, X2idn: Extreme memory for SAP HANA and large-scale in-memory applications - z1d: High compute and memory for EDA and database workloads
Storage Optimized (I, D, H series) - I3, I3en: High sequential read/write access to large datasets on local storage - D2, D3: Dense storage for data warehousing and distributed file systems - H1: High disk throughput for MapReduce and HDFS
Accelerated Computing (P, G, Inf, Trn series) - P4, P3: GPU instances for machine learning training - G4, G5: Graphics-intensive applications and ML inference - Inf1, Inf2: AWS Inferentia chips for ML inference - Trn1: AWS Trainium chips for ML training
How EC2 Instance Types Work
Each instance type follows a naming convention: [Family][Generation][Additional Capabilities].[Size]
For example, m5a.xlarge: - m = General Purpose family - 5 = Fifth generation - a = AMD processor - xlarge = Size (vCPUs and memory)
Common capability indicators: - a: AMD processors - n: Higher network bandwidth - d: Local NVMe storage - g: AWS Graviton (ARM) processors - z: High frequency
Instance sizes scale from nano to metal, with each size doubling resources from the previous.
T-Series Burstable Instances
T-series instances use CPU credits for burstable performance: - Instances earn credits when idle (below baseline) - Credits are spent when CPU usage exceeds baseline - T2/T3 Unlimited mode allows sustained high CPU (charges apply) - Monitor with CloudWatch metrics: CPUCreditUsage, CPUCreditBalance, CPUSurplusCreditBalance
Exam Tips: Answering Questions on EC2 Instance Types
1. Match the Workload to the Family - Web servers with variable traffic → T3 (burstable) - Databases requiring high memory → R series - Video encoding or batch processing → C series - Big data and analytics with local storage → I3 or D series - Machine learning training → P series - SAP HANA workloads → X series
2. Cost Optimization Questions - If a workload has consistent CPU usage below baseline, T instances are cost-effective - For steady-state workloads, consider M series over T series - Graviton (g suffix) instances offer better price-performance
3. Performance Troubleshooting - Application running slow on T2? Check CPU credit balance - Need more network throughput? Look for 'n' suffix instances - Storage bottleneck? Consider instances with 'd' suffix for local NVMe
4. Key Scenarios to Remember - Question mentions in-memory caching (Redis, Memcached) → R series - Question mentions high-performance computing → C series - Question mentions graphics rendering → G series - Question mentions data warehousing with high I/O → I3 or D series - Question mentions variable or unpredictable workloads → T series
5. Remember Instance Store vs EBS - Instances with 'd' suffix have ephemeral NVMe storage - Data on instance store is lost when instance stops - Use for temporary data, caches, or scratch data
6. Watch for Trick Questions - Newer generations (higher numbers) typically offer better performance per dollar - Not all instance types are available in all regions - Some instance types require specific AMIs (Graviton needs ARM-compatible)
7. CloudWatch Metrics to Know - CPUUtilization for sizing decisions - CPUCreditBalance for T-series troubleshooting - NetworkIn/NetworkOut for network-bound applications - EBSReadOps/EBSWriteOps for storage-bound workloads