Fluentd vs rsyslog
Fluentd
fluentd.orgrsyslog
rsyslog.comSide by side
| Figure | Fluentd | rsyslog |
|---|---|---|
| Price from | Free | €166.58/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | Yes | — |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 7 |
| Spec score · Telemetry Pipeline Software | 8.2 (#10) | 7.9 (#16) |
| Deployment options | self-hosted | The project offers source and Git installation paths, maintained packages for Ubuntu, RHEL/CentOS, and Debian, and a Docker container. |
| Founded | 2011 | 2004 |
| Integrations | Listed outputs include Elasticsearch and Kibana, Splunk, AWS S3, Kafka, BigQuery, Datadog, and OpenTelemetry. | Documented outputs include Elasticsearch and OpenSearch, Apache Kafka, HTTP endpoints, and syslog forwarding. |
| Purpose | Fluentd is an open source data collector for a unified logging layer. | rsyslog collects, transforms, and routes event data as a high-performance log processing engine. |
| Reliability | Fluentd supports memory and file buffering, failover, and high availability to help prevent inter-node data loss. | Features include on-demand disk spooling, backup destinations, and multiple processing threads. |
| Support | The project lists community help and commercial support from companies offering Fluentd enterprise services. | Community support is available through the mailing list, while Adiscon offers paid enterprise support for business users. |
Plans
rsyslog
- rsyslogFree
- Windows Agent Basic$55, paid once
- Windows Agent Professional$79, paid once
- Windows Agent Enterprise$109, paid once
- Enterprise Support€1,999 a year
- Extended Enterprise Support€3,899 a year
- Unlimited Enterprise Support€19,999 a year
In their own words
Fluentd
Fluentd is a free, open-source data collector for creating a unified logging layer. It uses JSON to handle log collection, filtering, buffering, and output across sources and destinations. More than 500 community plugins connect it to data sources and outputs, including Elasticsearch and Kibana, Splunk, AWS S3, Kafka, BigQuery, Datadog, and OpenTelemetry. It supports memory and file buffering, failover, and high availability to help prevent data loss between nodes. The project reports that a vanilla instance uses 30–40 MB of memory and can process 13,000 events per second per core. Fluentd v1 runs on Linux, Mac OSX, and Windows; community distributions also include Docker images, a Kubernetes DaemonSet, and Ruby gems. It is self-hosted, and its components are available under the Apache 2 License. The project lists community help and commercial support from companies offering enterprise services. The homepage notes vulnerabilities patched in Fluentd v1.19.3 and advises updating fluent-package to v6.0.4.
rsyslog
rsyslog is a self-hosted engine for collecting, transforming and routing event data, with a processing model built from inputs, rulesets and actions. The project says it can deliver over one million messages per second to local destinations when processing is limited. Reliability features include on-demand disk spooling, backup destinations and multiple processing threads. Documented outputs include Elasticsearch, OpenSearch, Apache Kafka, HTTP endpoints and syslog forwarding. Database outputs cover MariaDB/MySQL and PostgreSQL, with libdbi support for other databases. TLS-protected syslog and forwarding with peer authentication settings are documented. The core programs use GPLv3, while some runtime files use LGPL. rsyslog is developed for Linux, POSIX and related UNIX-like systems, and is available through source, Git, distribution packages and Docker. It does not run natively on Windows; a separate Windows Agent collects Event Logs and local log files and can relay syslog to rsyslog on Linux. The core software is free; paid support is available from €1,999/yr.