Grafana Alloy

Grafana Loki

grafana/loki

Popular

Log aggregation that indexes only labels to keep storage cheap; pairs with Grafana and Prometheus.

Elasticsearch

elastic/elasticsearch

Popular

Distributed search and analytics engine on Lucene, widely used for full-text, logs and vector search.

OpenSearch

opensearch-project/OpenSearch

Popular

Apache-licensed fork of Elasticsearch and Kibana, governed by the Linux Foundation's OpenSearch Foundation.

Fluent Bit

fluent/fluent-bit

Popular

Lightweight, high-performance log and telemetry processor; the default log agent in many Kubernetes setups.

Vector

vectordotdev/vector

High-performance Rust observability pipeline for collecting, transforming and routing logs and metrics.

Fluentd

fluent/fluentd

CNCF-graduated unified logging layer with 1,000+ plugins; heavier than Fluent Bit but very flexible.

Logstash

elastic/logstash

Elastic Stack's server-side pipeline for parsing and enriching logs before indexing in Elasticsearch.

Graylog

Graylog2/graylog2-server

Centralized log management with search, alerting and dashboards; popular on-prem and with security teams.

OpenObserve

openobserve/openobserve

Rising

Rust-based platform for logs, metrics and traces on object storage; a lightweight Elasticsearch alternative.