Graylog is a centralized logging solution that allows the user to aggregate and search 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.
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.
Please refer to the Graylog Docker documentation for a comprehensive overview and a detailed description of the Graylog Docker image.
If you simply want to checkout Graylog without any further customization, you can run the following three commands to create the necessary environment:
$ docker run --name mongo -d mongo:3
$ docker run --name elasticsearch \
-e "http.host=0.0.0.0" -e "xpack.security.enabled=false" \
-d docker.elastic.co/elasticsearch/elasticsearch:5.6.6
$ docker run --link mongo --link elasticsearch \
-p 9000:9000 -p 12201:12201 -p 514:514 \
-e GRAYLOG_WEB_ENDPOINT_URI="http://127.0.0.1:9000/api" \
-d graylog/graylog:2.4.3-1
Graylog comes with a default configuration that works out of the box but you have to set a password for the admin user. Also the web interface needs to know how to connect from your browser to the Graylog API. Both can be done via environment variables.
-e GRAYLOG_PASSWORD_SECRET=somepasswordpepper
-e GRAYLOG_ROOT_PASSWORD_SHA2=8c6976e5b5410415bde908bd4dee15dfb167a9c873fc4bb8a81f6f2ab448a918
-e GRAYLOG_WEB_ENDPOINT_URI="http://127.0.0.1:9000/api"
In this case you can login to Graylog with the user and password admin. Generate your own password with this command:
$ echo -n yourpassword | shasum -a 256
This all can be put in a docker-compose file, like:
version: '2'
services:
# MongoDB: https://hub.docker.com/_/mongo/
mongo:
image: mongo:3
# Elasticsearch: https://www.elastic.co/guide/en/elasticsearch/reference/5.5/docker.html
elasticsearch:
image: docker.elastic.co/elasticsearch/elasticsearch:5.6.6
environment:
- http.host=0.0.0.0
# Disable X-Pack security: https://www.elastic.co/guide/en/elasticsearch/reference/5.5/security-settings.html#general-security-settings
- xpack.security.enabled=false
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
ulimits:
memlock:
soft: -1
hard: -1
mem_limit: 1g
# Graylog: https://hub.docker.com/r/graylog/graylog/
graylog:
image: graylog/graylog:2.4.3-1
environment:
# CHANGE ME!
- GRAYLOG_PASSWORD_SECRET=somepasswordpepper
# Password: admin
- GRAYLOG_ROOT_PASSWORD_SHA2=8c6976e5b5410415bde908bd4dee15dfb167a9c873fc4bb8a81f6f2ab448a918
- GRAYLOG_WEB_ENDPOINT_URI=http://127.0.0.1:9000/api
links:
- mongo
- elasticsearch
ports:
# Graylog web interface and REST API
- 9000:9000
# Syslog TCP
- 514:514
# Syslog UDP
- 514:514/udp
# GELF TCP
- 12201:12201
# GELF UDP
- 12201:12201/udp
After starting the three containers with docker-compose up open your browser with the URL http://127.0.0.1:9000 and login with admin:admin
In order to make the log data and configuration of Graylog persistent, you can use external volumes to store all data. In case of a container restart simply re-use the existing data from the former instances.
If you need to customize the configuration files for Graylog (such as the Log4j 2 configuration), you can download the vanilla files from GitHub and put them into a dedicated Docker volume.
Create the configuration directory and copy the default files:
mkdir -p ./graylog/config
cd ./graylog/config
wget https://raw.githubusercontent.com/Graylog2/graylog2-images/2.4/docker/config/graylog.conf
wget https://raw.githubusercontent.com/Graylog2/graylog2-images/2.4/docker/config/log4j2.xml
The docker-compose.yml file looks like this:
version: '2'
services:
# MongoDB: https://hub.docker.com/_/mongo/
mongo:
image: mongo:3
volumes:
- mongo_data:/data/db
# Elasticsearch: https://www.elastic.co/guide/en/elasticsearch/reference/5.5/docker.html
elasticsearch:
image: docker.elastic.co/elasticsearch/elasticsearch:5.6.6
volumes:
- es_data:/usr/share/elasticsearch/data
environment:
- http.host=0.0.0.0
- transport.host=localhost
- network.host=0.0.0.0
# Disable X-Pack security: https://www.elastic.co/guide/en/elasticsearch/reference/5.5/security-settings.html#general-security-settings
- xpack.security.enabled=false
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
ulimits:
memlock:
soft: -1
hard: -1
mem_limit: 1g
# Graylog: https://hub.docker.com/r/graylog/graylog/
graylog:
image: graylog/graylog:2.4.3-1
volumes:
- graylog_journal:/usr/share/graylog/data/journal
- ./graylog/config:/usr/share/graylog/data/config
environment:
# CHANGE ME!
- GRAYLOG_PASSWORD_SECRET=somepasswordpepper
# Password: admin
- GRAYLOG_ROOT_PASSWORD_SHA2=8c6976e5b5410415bde908bd4dee15dfb167a9c873fc4bb8a81f6f2ab448a918
- GRAYLOG_WEB_ENDPOINT_URI=http://127.0.0.1:9000/api
links:
- mongo
- elasticsearch
ports:
# Graylog web interface and REST API
- 9000:9000
# Syslog TCP
- 514:514
# Syslog UDP
- 514:514/udp
# GELF TCP
- 12201:12201
# GELF UDP
- 12201:12201/udp
# Volumes for persisting data, see https://docs.docker.com/engine/admin/volumes/volumes/
volumes:
mongo_data:
driver: local
es_data:
driver: local
graylog_journal:
driver: local
Start all services with:
docker-compose up
Every configuration option can be set via environment variables, take a look here for an overview. Simply prefix the parameter name with GRAYLOG_ and put it all in upper case. Another option would be to store the configuration file outside of the container and edit it directly.
Documentation for Graylog is hosted here. Please read through the docs and familiarize yourself with the functionality before opening an issue on GitHub.
This Docker image is licensed under the Apache 2.0 license, see LICENSE.
Graylog itself is licensed under the GNU Public License 3.0, see license information.