docker-librenms

Docker image for LibreNMS

⚠️ This document refers to the master branch and does not necessarily correspond to the version that you are running. It is recommended to extract the readme from your preferred release's source code archive. Releases are listed on the Releases page.

About

docker-librenms is a customizable Docker image for LibreNMS based on Ubuntu.

The container runs nginx 1.15+ with HTTP/2 support and PHP 7.4 FPM with OPCache and rrdcached for maximum performance.

⚠️ ARM is not supported currently, see here for more details.

Initial setup

1.1. Generating an encryption key

You must first generate a unique encryption key.

Generating the key

docker run --rm jarischaefer/docker-librenms generate_key

Output example

base64:Q0+ZV56/5Uwz79vsvS4ZfwQFOty3e9DJEouEy+IXvz8=

⚠️ Make sure you keep the key secret, because anyone in possession of it can decrypt sensitive data.

1.2. Passing the encryption key

There are currently two methods to pass the encryption key to LibreNMS. Make sure to include the full key (including base64:) regardless of the method used.

1.2.1. Passing the key directly via environment variable

The key can be passed via the APP_KEY environment variable in the docker run command.

Example

The following command is incomplete and only illustrates passing an environment variable:

docker run -e APP_KEY=base64:Q0+ZV56/5Uwz79vsvS4ZfwQFOty3e9DJEouEy+IXvz8= jarischaefer/docker-librenms

1.2.2. Passing the key via a secret file

Alternatively, you may use the APP_KEY_FILE environment variable and mount the secret as a file inside the container. You must first create the file on the host and only then start the container (otherwise Docker creates and mounts a directory instead of a file).

Example

The following command is incomplete and only illustrates passing an environment variable and mounting a file:

docker run -e APP_KEY_FILE=/mount/secret_key -v /path/on/host/secret_key:/mount/secret_key

2.1. Database - Prerequisites

If you don't have a MySQL server setup either in Docker or elsewhere then you can create a docker container here.

You should read the LibreNMS installation docs for the latest instructions regarding database setup.

As of July 2020, the following settings are required (should apply to both MariaDB and MySQL):

innodb_file_per_table=1
lower_case_table_names=0

2.2. Database - Creating LibreNMS tables

You should have a MySQL server running at this point. Make sure the database, user and permissions exist before running the commands.

Next, follow the instructions for running the container. Once the container is up and running, you may use the following commands to populate the database and create an admin user.

Creating the tables

docker exec librenms setup_database

3.1. LibreNMS - Adding users

Creating an initial admin user

docker exec librenms create_admin

This creates a user with the following properties:

• User: admin
• Password: admin
• Level: 10
• E-Mail: [email protected]

Creating a custom user

docker exec librenms create_user user password level email

Example:

docker exec librenms create_user test test 10 [email protected]

Running the container

The examples below do not cover all of the available configuration options, check the appropriate section in the docs for a complete list.

Linked database container

In the example below the linked container is named my-database-container and its alias inside the container is database. Make sure my-database-container matches the MySQL container's name and DB_HOST matches its alias inside the container if you intend to modify it.

docker run \
	-d \
	-h librenms \
	-p 80:80 \
	-e APP_KEY=the_secret_key_you_have_generated \
	-e DB_HOST=database \
	-e DB_NAME=librenms \
	-e DB_USER=librenms \
	-e DB_PASS=secret \
	-e BASE_URL=http://localhost \
	--link my-database-container:database \
	-v /data/logs:/opt/librenms/logs \
	-v /data/rrd:/opt/librenms/rrd \
	--name librenms \
	jarischaefer/docker-librenms

Remote database

docker run \
	-d \
	-h librenms \
	-p 80:80 \
	-e APP_KEY=the_secret_key_you_have_generated \
	-e DB_HOST=x.x.x.x \
	-e DB_NAME=librenms \
	-e DB_USER=librenms \
	-e DB_PASS=secret \
	-e BASE_URL=http://localhost \
	-v /data/logs:/opt/librenms/logs \
	-v /data/rrd:/opt/librenms/rrd \
	--name librenms \
	jarischaefer/docker-librenms

SSL

Mount another directory containing ssl.key, ssl.crt and optionally ssl.ocsp.crt to enable HTTPS. You'll also have to change BASE_URL.

docker run \
	-d \
	-h librenms \
	-p 80:80 \
	-p 443:443 \
	-e APP_KEY=the_secret_key_you_have_generated \
	-e DB_HOST=database \
	-e DB_NAME=librenms \
	-e DB_USER=librenms \
	-e DB_PASS=secret \
	-e BASE_URL=https://localhost \
	--link my-database-container:database \
	-v /data/logs:/opt/librenms/logs \
	-v /data/rrd:/opt/librenms/rrd \
	-v /data/ssl:/etc/nginx/ssl:ro \
	--name librenms \
	jarischaefer/docker-librenms

Updating the container

Updating an existing installation requires updating both the image and the database.

1.1. Image update - Pulling a new version

1. Pick a release from the Releases page
2. Run docker pull jarischaefer/docker-librenms:{release}
3. Restart your container using the new version
4. Follow the steps for database updates

1.2. Database update

Automatic database updates are the most convenient solution for single-container setups.

1.2.1. Manual database updates (safe)

Run docker exec librenms setup_database.

1.2.2. Automatic database updates (potentially unsafe)

If you would like to update the database automatically on startup, you may pass DAILY_ON_STARTUP=true. Keep in mind that restarting more than one container simultaneously could result in concurrency issues and damage your database.

The LibreNMS implementation (as of October 2018) uses a distributed lock via memcache to avoid this scenario. Therefore, if all containers share the same memcache instance, concurrent restarts would be safe.

Configuration

⚠️ The container must be stopped, removed and subsequently restarted in order for configuration changes to take effect.

The following keys can be passed directly via the -e switch:

Basic configuration

Enabling/disabling container features

Enabling/disabling LibreNMS features

Custom configuration

You may apply custom configuration by mounting files matching *.php in /opt/librenms/conf.d.

In the example below /data/config.interfaces.php on the host is mounted inside the container at /opt/librenms/conf.d/config.interfaces.php.

docker run \
	-d \
	-h librenms \
	-p 80:80 \
	-p 443:443 \
	-e APP_KEY=the_secret_key_you_have_generated \
	-e DB_HOST=database \
	-e DB_NAME=librenms \
	-e DB_USER=librenms \
	-e DB_PASS=secret \
	-e BASE_URL=https://localhost \
	--link my-database-container:database \
	-v /data/logs:/opt/librenms/logs \
	-v /data/rrd:/opt/librenms/rrd \
	-v /data/ssl:/etc/nginx/ssl:ro \
	-v /data/config.interfaces.php:/opt/librenms/conf.d/config.interfaces.php \
	--name librenms \
	jarischaefer/docker-librenms

config.interfaces.php

<?php

$config['bad_if_regexp'][] = '/^docker[-\w].*$/';
$config['bad_if_regexp'][] = '/^lxcbr[0-9]+$/';
$config['bad_if_regexp'][] = '/^veth.*$/';
$config['bad_if_regexp'][] = '/^virbr.*$/';
$config['bad_if_regexp'][] = '/^lo$/';
$config['bad_if_regexp'][] = '/^macvtap.*$/';
$config['bad_if_regexp'][] = '/gre.*$/';
$config['bad_if_regexp'][] = '/tun[0-9]+$/';

Disabling cron jobs or the local rrdcached instance

If you plan to use this container for a distributed LibreNMS installation, you may want to disable some of the default cron jobs, or the local rrdcached, nginx and php-fpm services. You could also increase the number of discovery-wrapper.py threads.

docker run \
	-d \
	-h librenms \
	-p 80:80 \
	-e APP_KEY=the_secret_key_you_have_generated \
	-e DB_HOST=database \
	-e DB_NAME=librenms \
	-e DB_USER=librenms \
	-e DB_PASS=secret \
	-e BASE_URL=http://localhost \
	-e POLLERS=16 \
	-e TZ=UTC \
	-e DISCOVERY_THREADS=2 \
	-e DAILY_ENABLE=false \
	-e ALERTS_ENABLE=false \
	-e CHECK_SERVICES_ENABLE=false \
	-e RRDCACHED_ENABLE=false \
	-e NGINX_ENABLE=false \
	-e PHPFPM_ENABLE=false \
	--link my-database-container:database \
	-v /data/logs:/opt/librenms/logs \
	-v /data/rrd:/opt/librenms/rrd \
	--name librenms \
	jarischaefer/docker-librenms

Custom Nagios plugins

Nagios plugins are stored in /usr/lib/nagios/plugins. Choose one of the options below if you would like to add new plugins. See the corresponding issue for more information.

Option 1 (recommended)

1. Mount a new directory to /mount/nagios_plugins. Example (using Docker CLI): -v /nagios_plugins:/mount/nagios_plugins
2. Copy the new plugins to /nagios_plugins on the host
3. Restart the container and verify that the files exist: docker exec librenms ls -al /usr/lib/nagios/plugins

The container will automatically symlink the contents of /mount/nagios_plugins to /usr/lib/nagios/plugins.

Example

docker exec librenms ls -al /usr/lib/nagios/plugins/check_xyz

lrwxrwxrwx 1 root root 31 Jan 21 22:19 /usr/lib/nagios/plugins/check_xyz -> /mount/nagios_plugins/check_xyz

Option 2

Make sure the plugin (file) exists on the host before starting the container (Docker creates a directory on startup by default). Each plugin must be mounted individually (-v for Docker CLI), for example: -v /nagios_plugins/check_xyz:/usr/lib/nagios/plugins/check_xyz

Executing commands inside the container

Make sure you source the environment variables from /etc/librenms_environment prior to executing commands inside the container.

This is an example demonstrating how to run the validation script.

su - librenms
source /etc/librenms_environment
cd /opt/librenms
php validate.php

Running in production

The commands above are purely for illustrative purposes. You should customize them to fit your environment.

Also, please note that...

• Alerting via email is supported via SMTP only.
• Publicly accessible installations should be put behind jwilder/nginx-proxy or similar proxies for better access control and security hardening.

syslog

These are instructions for the LibreNMS syslog extension.

• Add -e ENABLE_SYSLOG=true to your docker run command
• Add -p 514:514 and -p 514:514/udp to your docker run command
• Configure the remote host whose logs should be gathered (rsyslog example)
  • Create /etc/rsyslog.d/60-librenms.conf
  • Add *.* @example.com:514

Unfortunately, due to the way Docker works (more specifically, its network modes), the devices and IP addresses visible in LibreNMS may not be what one would expect. Instead of displaying the host's real IP address, it is possible that an internal address such as 172.17.0.1 is observed. More information regarding this behavior can be found in the corresponding issue.

Weathermap

These are instructions for the LibreNMS weathermap plugin.

The weathermap plugin requires additional mounts to persist its data.

• /opt/librenms/html/plugins/Weathermap/configs for the configs
• /opt/librenms/html/plugins/Weathermap/output for the generated data

Make sure you set Output Image Filename to output/example.png and Output HTML Filename to output/example.html in the Map Properties configuration section so the files are persisted in the output directory.

License

This project is open-sourced software licensed under the MIT license.

LibreNMS has its own license, this license only covers the Docker part.