Amazon OpenSearch Ingestion vs Fluent Bit

Amazon OpenSearch Ingestion is a managed, serverless service that streams logs, metrics, and traces to OpenSearch Service domains or OpenSearch Serverless collections. Each pipeline has a source, optional ordered processors, and one or more sinks, including another pipeline as a sink. Processing can filter, enrich, transform, normalize, aggregate, and route structured or unstructured data, including textual, numerical, and geospatial content. AWS automatically scales ingestion workloads and manages installation, patching, version upgrades, continuous monitoring, and repair. Users define YAML pipelines through the AWS Console or CLI, set minimum and maximum ingestion OCU capacity, or pause a pipeline; paused pipelines consume no OCUs. Billing is hourly with per-minute granularity for allocated OCUs, with one OCU providing 15 GB RAM and 2 vCPU. Private connectivity is available through VPC access and PrivateLink, or pipelines can use the public internet. Redaction, obfuscation, conditional routing, and a stated 99.9% availability SLA are included.

Fluent Bit is a free, open-source telemetry agent for collecting and processing logs, metrics, and traces. It can run as an edge agent on constrained systems or as a central collector for cloud infrastructure, and is designed for high throughput with low resource consumption. Built-in parsers cover JSON, Regex, LTSV, and Logfmt; metrics compatibility includes Prometheus and OpenTelemetry. More than 100 built-in plugins cover inputs, filters, analytics, and outputs, with destinations including Splunk, Elasticsearch, OpenSearch, and Kafka. Buffering in memory or on the file system and backpressure handling support data flow, while network input and output plugins include TLS and SSL. Stream processing supports SQL queries, aggregation windows, forecasting, and data analysis. Users can write plugins in C, Lua, Golang, or WebAssembly. The Open-source Fluent Bit plan costs nothing, with self-hosted deployment under the Apache License 2.0. Official packages and installation guidance cover Linux, macOS, Windows, containers, and selected BSD and IBM Z Linux environments.