Graylog Docker image

The latest stable version of Graylog is 4.2.3, which is available via tags 4.2, 4.2.3, and 4.2.3-1.

Consider using the stable 4.2 release for your production environments. Please check the Graylog Docker documentation for complete installation and configuration instructions.

What is Graylog?

Graylog is a centralized logging solution that enables aggregating and searching through logs. It provides a powerful query language, a processing pipeline for data transformation, alerting abilities, and much more. It is fully extensible through a REST API. Add-ons can be downloaded from the Graylog Marketplace.

Architecture

Take a look at the minimal Graylog architecture to get the big picture of a Graylog setup. In essence, Graylog needs to talk to MongoDB to store configuration data as well as Elasticsearch to store the actual log data.

Configuration

Please refer to the Graylog Docker documentation for a comprehensive overview and detailed description of the Graylog Docker image.

If you want to quickly spin up an instance for testing, you can use our Docker Compose template.

Notably, this image requires that two important configuration options be set (although in practice you will likely need to set more):

1. password_secret (environment variable GRAYLOG_PASSWORD_SECRET)
   • A secret that is used for password encryption and salting.
   • Must be at least 16 characters, however using at least 64 characters is strongly recommended.
   • Must be the same on all Graylog nodes in the cluster.
   • May be generated with something like: pwgen -N 1 -s 96
2. root_password_sha2 (environment variable GRAYLOG_ROOT_PASSWORD_SHA2)
   • A SHA2 hash of a password you will use for your initial login as Graylog's root user.
     • The default username is admin. This value is customizable via configuration option root_username (environment variable GRAYLOG_ROOT_USERNAME).
   • In general, these credentials will only be needed to initially set up the system or reconfigure the system in the event of an authentication backend failure.
   • This password cannot be changed using the API or via the Web interface.
   • May be generated with something like: echo -n "Enter Password: " && head -1 </dev/stdin | tr -d '\n' | sha256sum | cut -d" " -f1

Every Graylog configuration option can be set via environment variable. To get the environment variable name for a given configuration option, simply prefix the option name with GRAYLOG_ and put it all in upper case. Another option is to store the configuration file outside of the container and edit it directly.

This image includes the wait-for-it script, which allows you to have Docker wait for Elasticsearch to start up before starting Graylog. For example, if you are using Docker Compose you could override the entrypoint for Graylog like this:

entrypoint: /usr/bin/tini -- wait-for-it elasticsearch:9200 -- /docker-entrypoint.sh

Image Details

There are several different image variants available. These images run on Debian and Java 8. For the graylog and graylog-enterprise images, there are also ARM64 and Java 11 variants.

graylog:<version>

This is the open source Graylog image. Check the Docker Hub page for a list of all available versions.

graylog-enterprise:<version>

This is the Graylog Enterprise image. Check the Docker Hub page for a list of all available versions.

graylog-forwarder:<version>

This image runs the Graylog Forwarder. Check the Docker Hub page for a list of all available versions.

Documentation

Documentation for Graylog is hosted here. Please read through the docs and familiarize yourself with the functionality before opening an issue on GitHub.

License

Graylog itself is licensed under the Server Side Public License (SSPL), see license information.

This Docker image is licensed under the Apache 2.0 license, see LICENSE.