### Module 6: Scalability and High Availability #### Lesson 1: Strategies for Scaling (Vertical vs. Horizontal Scaling) **Objective**: Introduce participants to scaling strategies for OpenSearch clusters and the implications of each approach. **Topics**: - **Understanding Scalability**: Definition and importance of scalability in the context of OpenSearch. - **Vertical Scaling**: Advantages and limitations of scaling up (increasing the capacity of existing nodes), including when and how to effectively use vertical scaling. - **Horizontal Scaling**: Exploring the benefits and challenges of scaling out (adding more nodes to a cluster) and best practices for horizontal scaling. - **Decision Factors**: Criteria to consider when choosing between vertical and horizontal scaling, including cost implications, performance benefits, and operational complexity. #### Lesson 2: Designing for High Availability (Replica Strategies, Cross-Region Replication) **Objective**: Explore strategies to design OpenSearch clusters for high availability, ensuring continuous operation and data durability. **Topics**: - **High Availability Concepts**: Introduction to high availability and its importance for OpenSearch clusters. - **Replica Strategies**: How to use replicas effectively to enhance cluster availability and fault tolerance, including optimal replica counts and distribution. - **Cross-Region Replication**: Advantages of cross-region replication for disaster recovery and global availability, including how to set up and manage cross-region replicas in OpenSearch. - **Handling Failures**: Strategies for detecting and recovering from node and network failures, including the role of master nodes in cluster health and recovery processes. #### Lesson 3: Implementing Auto-Scaling Solutions **Objective**: Guide participants through the implementation of auto-scaling solutions for OpenSearch clusters to dynamically adjust resources in response to load variations. **Topics**: - **Auto-Scaling Basics**: Overview of auto-scaling and its benefits for managing OpenSearch clusters. - **Auto-Scaling Triggers**: Identifying key metrics and thresholds that can trigger auto-scaling actions, such as CPU utilization, memory pressure, and search/indexing throughput. - **Configuring Auto-Scaling**: Step-by-step guidance on setting up auto-scaling policies for OpenSearch clusters, including considerations for cooldown periods and scaling limits. - **Integration with Cloud Platforms**: For clusters hosted on cloud platforms, an overview of integrating OpenSearch auto-scaling with services like AWS Auto Scaling Groups. **Engagement Activities**: - **Interactive Workshop**: Participants will configure auto-scaling for an OpenSearch cluster using a cloud platform's management console or CLI, setting up scaling policies based on simulated load patterns. - **Discussion and Analysis**: Reflect on the auto-scaling setup process, challenges encountered, and strategies for optimizing auto-scaling policies to balance performance and cost.