syslog-ng is an enhanced log daemon, supporting a wide range of input and output methods: syslog, unstructured text, message queues, databases (SQL and NoSQL alike), and more.
The simplest configuration accepts system logs from /dev/log (from applications or forwarded by systemd) and writes everything to a single file:
@version: 4.8
@include "scl.conf"
log {
source { system(); };
destination { file("/var/log/syslog"); };
};
This one additionally processes logs from the network (TCP/514 by default):
@version: 4.8
@include "scl.conf"
log {
source {
system();
network();
};
destination { file("/var/log/syslog"); };
};
This config is designed for structured/application logging, using local submission via JSON, and outputting in key=value format:
@version: 4.8
@include "scl.conf"
log {
source { system(); };
destination { file("/var/log/app.log" template("$(format-welf --subkeys .cim.)\n")); };
};
To submit a structured log using logger
, you might run:
$ logger '@cim: {"name1":"value1", "name2":"value2"}'
In which case the resulting message will be:
name1=value1 name2=value2
For a brief introduction to configuring the syslog-ng application, see the quickstart guide.
- Receive and send RFC3164 and RFC5424 style syslog messages
- Receive and send JSON formatted messages
- Work with any kind of unstructured data
- Classify and structure logs using built-in parsers (csv-parser(), db-parser(), kv-parser(), etc.)
- Normalize, crunch, and process logs as they flow through the system
- Hand over logs for further processing using files, message queues (like AMQP), or databases (like PostgreSQL or MongoDB)
- Forward logs to big data tools (like Elasticsearch, Apache Kafka, or Apache Hadoop)
- syslog-ng provides performance levels comparable to a large cluster when running on a single node
- In the simplest use case, it scales up to 600-800k messages per second
- But classification, parsing, and filtering still produce several tens of thousands of messages per second
- syslog-ng is developed by a community of volunteers, the best way to contact us is via our github project page project, our gitter channel or our mailing list.
- syslog-ng is integrated into almost all Linux distributions and BSDs, it is also incorporated into a number of products, see our powered by syslog-ng page for more details.
- Balabit is the original commercial sponsor of the syslog-ng project, and was acquired by One Identity in 2018. One Identity offers a commercial edition for syslog-ng, called the syslog-ng Premium Edition.
- Axoflow is the company of Balazs Scheidler, the original creator and main developer of syslog-ng.
We are really interested to see who uses our software, so if you do use it and you like what you see, please tell us about it. A star on github or an email saying thanks means a lot already, but telling us about your use case, your experience, and things to improve would be much appreciated.
Just send an email to feedback (at) syslog-ng.org.
Feedback Powers Open Source.
Releases and precompiled tarballs are available on GitHub.
To compile from source, the easiest is to use dbld
, a docker based,
self-hosted compile/build/release infrastructure within the source tree. See
dbld/README.md
for more information.
For the brave souls who want to compile syslog-ng from scratch, the usual drill applies:
$ ./configure && make && make install
The extra effort in contrast with the dbld based build is the need to fetch and install all build dependencies of syslog-ng (of which there are a few).
If you don't have a configure script (because of cloning from git, for example),
run ./autogen.sh
to generate it.
Some of the functionality of syslog-ng is compiled only if the required development libraries are present. The configure script displays a summary of enabled features at the end of its run. For details, see the syslog-ng compiling instructions.
Binaries are available in various Linux distributions and contributors maintain packages of the latest and greatest syslog-ng version for various OSes.
Simply invoke the following command as root:
# apt install syslog-ng
The latest versions of syslog-ng are available for a wide range of Debian and Ubuntu releases from our APT repository.
The packages and the APT repository are provided "as is" without warranty of any kind, on a best-effort level.
syslog-ng packages are released for the following distribution versions (x86-64):
Distro version | sources.list component name |
---|---|
Ubuntu 24.04 | ubuntu-noble |
Ubuntu 23.10 | ubuntu-mantic |
Ubuntu 23.04 | ubuntu-lunar |
Ubuntu 22.04 | ubuntu-jammy |
Ubuntu 20.04 | ubuntu-focal |
Debian 12 | debian-bookworm |
Debian 11 | debian-bullseye |
Debian Unstable | debian-sid |
Debian Testing | debian-testing |
-
Download and install the release signing key:
wget -qO - https://ose-repo.syslog-ng.com/apt/syslog-ng-ose-pub.asc | sudo apt-key add -
-
Add the repository containing the latest build of syslog-ng to the APT sources. For example, stable releases on Ubuntu 22.04:
echo "deb https://ose-repo.syslog-ng.com/apt/ stable ubuntu-noble" | sudo tee -a /etc/apt/sources.list.d/syslog-ng-ose.list
-
Run
apt update
Nightly packages are built and released from the git master
branch everyday.
Use nightly
instead of stable
in step 2 to use the nightly APT repository. E.g.:
echo "deb https://ose-repo.syslog-ng.com/apt/ nightly ubuntu-noble" | sudo tee -a /etc/apt/sources.list.d/syslog-ng-ose.list
Nightly builds can be used for testing purposes (obtaining new features and bugfixes) at the risk of breakage.
# pacman -S syslog-ng
syslog-ng is available as a Fedora package that you can install using dnf:
You can download packages for the latest versions from here.
For instructions on how to install syslog-ng on RPM distributions, see the blog post Installing latest syslog-ng on RHEL and other RPM distributions.
If you wish to install the latest RPM package that comes from a recent commit in Git for testing purposes, read the blog post, RPM packages from syslog-ng Git HEAD.
# brew install syslog-ng
Binaries for other platforms are listed on the official third party page.
Binaries are also available as a Docker image. To find out more, check out the blog post, Your central log server in Docker.
For the latest, markdown based version, see the syslog-ng documentation center.
The official documentation of the earlier versions (3.X) of syslog-ng Open Source Edition provided by One Identity is available
here.
If you would like to contribute to syslog-ng, to fix a bug or create a new module, the syslog-ng pages helps you take the first steps to working with the code base.