This curriculum spans the equivalent depth and breadth of a multi-workshop operational immersion, covering the full lifecycle of indexing in ELK—from ingestion through sharding, security, and recovery—with the same technical specificity found in internal platform engineering playbooks.
Module 1: Understanding Data Ingestion Patterns in ELK
- Select and configure Logstash input plugins based on source system protocols (e.g., syslog, Beats, JDBC) while managing connection timeouts and backpressure.
- Design filebeat prospector configurations to monitor log rotation patterns without duplicating or missing events.
- Implement JSON parsing in Logstash filters only when schema stability is confirmed; otherwise, use grok patterns with error handling.
- Configure Kafka as an ingestion buffer between data sources and Logstash to handle ingestion spikes and enable replayability.
- Choose between Filebeat lightweight shipping and Logstash heavy transformation based on CPU constraints at the edge.
- Validate timestamp extraction logic in Logstash to prevent misalignment in time-based indices due to timezone or format mismatches.
- Set up conditional pipelines in Logstash to route data by type (e.g., application logs vs. audit trails) before indexing.
Module 2: Index Design and Sharding Strategy
- Determine primary shard count at index creation based on anticipated data volume and node count, knowing it cannot be changed later.
- Size shards between 10–50 GB to balance search performance and cluster management overhead.
- Implement time-based index naming (e.g., logs-2024-04-01) to support index lifecycle management and faster deletions.
- Use index templates to enforce consistent mappings, settings, and shard allocation across dynamically created indices.
- Allocate replica shards considering availability requirements versus storage cost, especially in multi-zone deployments.
- Prevent shard sprawl by consolidating low-volume data streams using data streams and ILM rollover policies.
- Adjust refresh_interval per index based on search latency requirements—lower for real-time dashboards, higher for batch logs.
Module 3: Mapping and Schema Management
- Define explicit field mappings for high-cardinality fields (e.g., user IDs) to avoid dynamic mapping explosions.
- Use keyword and text field types appropriately: keyword for aggregations/filters, text for full-text search.
- Disable _all field and limit field expansion in mappings to reduce indexing overhead and index size.
- Set norms: false on fields not used in scoring to save disk and memory in large indices.
- Implement index templates with dynamic templates to auto-apply settings based on field name patterns (e.g., *ip → ip type).
- Freeze index mappings after stabilization to prevent unintended schema drift from application changes.
- Monitor mapping conflicts in multi-pipeline environments where different sources write to the same index pattern.
Module 4: Index Lifecycle Management (ILM)
- Define ILM policies with hot, warm, cold, and delete phases aligned to data access patterns and compliance requirements.
- Trigger rollover based on index size or age, ensuring no single index exceeds performance thresholds.
- Rebalance indices from hot to warm nodes by updating shard allocation filters after rollover.
- Freeze cold indices to reduce JVM heap usage while retaining searchability for audit access.
- Set up forcemerge and shrink operations in the warm phase for large read-only indices.
- Automate snapshot creation before the delete phase for regulatory retention and disaster recovery.
- Monitor ILM explain API to troubleshoot failed transitions and policy violations.
Module 5: Data Stream Architecture and Management
- Convert time-series indices to data streams to simplify management of write indices and rollover behavior.
- Configure data stream templates with matching index templates to enforce settings across backing indices.
- Use _data_stream API to monitor active write indices and detect ingestion bottlenecks.
- Manage privileges for data stream operations, ensuring producers can only write to allowed streams.
- Integrate data streams with Fleet-managed agents to standardize telemetry collection.
- Handle schema changes in data streams by updating the matching index template and rolling over to a new backing index.
- Monitor backing index count per data stream to avoid exceeding cluster-level index limits.
Module 6: Performance Optimization During Indexing
- Tune bulk request size and frequency in Logstash output to maximize throughput without triggering circuit breakers.
- Adjust thread_pool.write.queue_size on data nodes to buffer indexing load during peak ingestion.
- Disable refresh during bulk imports using ?refresh=false and restore afterward to accelerate indexing.
- Use _bulk API with proper error handling instead of individual index requests in custom applications.
- Preprocess and drop unnecessary fields in Logstash to reduce network and disk usage.
- Implement backoff and retry logic in clients to handle 429 (Too Many Requests) responses gracefully.
- Monitor indexing pressure metrics to detect sustained high load and adjust node resources.
Module 7: Security and Access Control for Indices
- Define role-based index privileges (read, write, delete) using Elasticsearch roles and map to LDAP/AD groups.
- Apply field- and document-level security to restrict sensitive data exposure in shared indices.
- Enable index encryption at rest for compliance with data protection regulations (e.g., GDPR, HIPAA).
- Use index aliases with restricted permissions to expose only relevant data to specific teams.
- Rotate API keys used for indexing pipelines on a scheduled basis and audit key usage.
- Log and monitor unauthorized index creation attempts using audit logging and watcher alerts.
- Isolate indices by tenant in multi-customer environments using index patterns and role wildcards.
Module 8: Monitoring, Alerting, and Index Health
- Track index growth rate using Kibana or custom queries to anticipate storage and shard allocation issues.
- Set up alerts for high indexing latency, shard failures, or unassigned replicas using Elasticsearch watcher.
- Use _cat APIs and Kibana Stack Monitoring to identify hot shards and rebalance uneven loads.
- Regularly audit index settings for deviations from organizational standards using ILM or scripts.
- Monitor merge throttling and disk I/O to detect indexing bottlenecks on data nodes.
- Validate snapshot integrity for indices containing critical data using periodic restore tests.
- Correlate indexing errors in Logstash logs with Elasticsearch cluster logs to isolate root causes.
Module 9: Disaster Recovery and Index Restoration
- Configure repository locations for snapshots with access controls and cross-cluster replication.
- Test full cluster and individual index restores from snapshots to validate recovery time objectives.
- Use partial restores to recover specific indices without overwriting healthy cluster state.
- Replicate critical indices to a separate cluster in another region using cross-cluster search or replication.
- Document and version control index templates and ILM policies to ensure consistency after rebuilds.
- Plan for UUID mismatches when restoring indices to different clusters by using alias-based references.
- Automate snapshot deletion based on retention policies to prevent unbounded storage growth.