This article provides a step-by-step guide for setting up CloudWatch agent and collectd on Amazon EC2 Linux instances to collect enhanced system metrics.

• collectd is an open-source daemon that collects system and application performance metrics from Linux
• CloudWatch agent can capture collectd data and send it to CloudWatch for monitoring and analysis
• Use AWS Systems Manager State Manager and Parameter Store to automate installation across multiple servers
• Configure collectd plugins (e.g., fhcount for open files) to collect specific metrics
• CloudWatch agent requires IAM permissions: CloudWatchAgentServerPolicy and AmazonSSMManagedInstanceCore
• Metrics appear in CloudWatch under custom namespace "CWAgent" with dimensions for host, type, and type_instance
• Create dashboards, alarms, and queries using Metric Insights and Metric Math for data visualization
• Supports anomaly detection alarms for identifying unusual metric behavior patterns

The guide demonstrates collecting open file handle metrics as an example, with detailed instructions for configuration, deployment via State Manager, and creating CloudWatch dashboards and alarms for monitoring.