Installation and Configuration

This section explains how to install and configure a new Horizon instance, including the following tasks:

Install all required OpenNMS Horizon components, including PostgreSQL, on a single node.
Run Horizon core and PostgreSQL with the default configuration.

The default configuration is not optimized to run in a production environment or monitor large networks.
- By default, your time series database is JRobin, which persists RRD files on the local file system.
Sign in to the web UI and change the admin account’s default password.

DNS considerations

If you are planning a large deployment, you may need to review your DNS configuration to ensure name lookups can be processed quickly. DNS lookups may be preformed by different processes, including while provisioning new nodes and when receiving syslog messages. It is vital that DNS lookups can be performed quickly to prevent them from becoming a bottleneck, which can happen if your deployment covers thousands of nodes. One way to mitigate DNS performance is to setup your Horizon as a secondary DNS server so that it is able to self-host DNS records for your network.

Quick installation

If you want to get started quickly with OpenNMS Horizon on a bare metal system or a virtual machine, you can check out our quick install scripts. This convenient script installs Horizon on Debian or Red Hat compatible systems, running the steps documented in this section of the deployment guide. Use this quick starting point to evaluate and explore how to configure Horizon before moving to more complex distributed environments.

Scope

Bootstrap a single-node Horizon system on RPM or DEB-based systems quickly, with the latest stable release.
Installation follows the best-practices from our official docs.
Script is only for new installs and does not deal with existing installations or upgrades.
Script does not configure or install Minions, Sentinels, or distributed time series storage like Newts or Cortex.

Requirements

The following components and settings are required to set up a new Horizon instance:

A Linux physical server, or a virtual machine running a supported Linux operating system.
Internet access to download the installation packages.
A working DNS server, and a localhost and server name that resolve properly.
A system user with administrative permissions (sudo) to perform installation.
A SELinux policy that permits binding to the ICMP service, if necessary.

If you do not include the appropriate SELinux policy, Horizon may generate an ICMP permissions error when starting up (see SELinux and ICMP permissions).
To run services in Docker, you need Docker Compose for the service stacks from our examples.
On Debian, you must install and configure sudo yourself. See the Debian Wiki for more information.

Time synchronization is a critical part of operating a monitoring system. Ensure you have a functional time synchronization process running with your operating system. If you are not familiar with this topic, the knowledgebase article Ensure time synchronization for your OpenNMS components is a good starting point.

Set up PostgreSQL

PostgreSQL 14 and 15 use the scram-sha-256 password authentication method by default. If you use older versions of PostgreSQL, you should change the method in postgresql.conf and in pg_hba.conf before installing the Horizon core instance.

Pool size and maximum database connections

You must configure the PostgreSQL max_connections setting to at least twice the maximum pool size in Horizon.

The default maximum pool size value in Horizon is 50, but it applies to each connect in opennms-datasources.xml: opennms (the main connection used at runtime) and opennms-admin (the connection used during administrative operations, including installation). Therefore, your max_connections setting should be at least 100.

If you change the default pool size, make sure you also update the max_connections. You typically set this in PG_HOME/data/postgresql.conf, but you may also use the ALTER SYSTEM syntax. You must restart the PostgreSQL server for the changes to take effect.

You may find PGTune useful to calculate configuration parameters for PostgreSQL. As with all third-party tools, we do not endorse or guarantee it. Use it at your own discretion.

CentOS/RHEL 9
CentOS/RHEL 8
CentOS/RHEL 7
Debian/Ubuntu
Docker

Install language packs and set language

sudo dnf install langpacks-en glibc-all-langpacks -y
sudo localectl set-locale LANG=en_US.UTF-8
sudo localectl
sudo dnf makecache
sudo dnf update -y
sudo reboot
sudo dnf info postgresql-server

These procedures use a specific PostgreSQL version. Make sure you reference your current PostgreSQL version.

Install PostgreSQL client and server

sudo dnf -y install https://download.postgresql.org/pub/repos/yum/reporpms/EL-9-x86_64/pgdg-redhat-repo-latest.noarch.rpm
sudo dnf -y install postgresql14-server

Initialize the PostgreSQL database

sudo /usr/pgsql-14/bin/postgresql-14-setup initdb

Enable PostgreSQL on system boot and start immediately

sudo systemctl enable --now postgresql-14

Create an opennms database user and password

sudo -i -u postgres createuser -P opennms

You must provide a secure password for the opennms database user account. This guide uses YOUR-OPENNMS-PASSWORD as a placeholder.

Create an empty database and set the owner to the opennms user

sudo -i -u postgres createdb -O opennms opennms

Set a password for PostgreSQL superuser

sudo -i -u postgres psql -c "ALTER USER postgres WITH PASSWORD 'YOUR-POSTGRES-PASSWORD';"

Change YOUR-POSTGRES-PASSWORD to a secure one. The superuser is required to be able to initialize and change the database schema for installation and updates.

Change the access policy for PostgreSQL

sudo vi /var/lib/pgsql/14/data/pg_hba.conf

Allow Horizon to access the database over the local network with an MD5 hashed password

host    all             all             127.0.0.1/32            md5 (1)
host    all             all             ::1/128                 md5 (1)

1	Change method from `ident` to `md5` for IPv4 and IPv6 on localhost.

Apply configuration changes for PostgreSQL

sudo systemctl reload postgresql-14

Install PostgreSQL client and server

sudo dnf -y install postgresql-server postgresql

Initialize the PostgreSQL database

sudo postgresql-setup --initdb --unit postgresql

Enable PostgreSQL on system boot and start immediately

sudo systemctl enable --now postgresql

Create an opennms database user and password

sudo -i -u postgres createuser -P opennms

You must provide a password for the opennms database user. This guide uses YOUR-OPENNMS-PASSWORD as a placeholder. Please set a secure password.

Create an empty database and set the owner to the opennms user

sudo -i -u postgres createdb -O opennms opennms

Set a password for PostgreSQL superuser

sudo -i -u postgres psql -c "ALTER USER postgres WITH PASSWORD 'YOUR-POSTGRES-PASSWORD';"

Change YOUR-POSTGRES-PASSWORD to a secure one. The superuser is required to be able to initialize and change the database schema for installation and updates.

Change the access policy for PostgreSQL

sudo vi /var/lib/pgsql/data/pg_hba.conf

Allow Horizon to access the database over the local network with an MD5 hashed password

host    all             all             127.0.0.1/32            md5(1)
host    all             all             ::1/128                 md5(1)

1	Change method from `ident` to `md5` for IPv4 and IPv6 on localhost.

Apply configuration changes for PostgreSQL

sudo systemctl reload postgresql

Add PostgreSQL 12 package repository

sudo yum -y install https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm

Install PostgreSQL 12 client and server

sudo yum -y install postgresql12-server postgresql12

Initialize PostgreSQL database

sudo /usr/pgsql-12/bin/postgresql-12-setup initdb

Enable PostgreSQL on system boot and start immediately

sudo systemctl enable --now postgresql-12

Create an opennms database user and password

sudo -i -u postgres createuser -P opennms

You must provide a password for the opennms database user. This guide uses YOUR-OPENNMS-PASSWORD as a placeholder. Please set a secure password.

Create an empty database and set the owner to the opennms user

sudo -i -u postgres createdb -O opennms opennms

Set a password for PostgreSQL superuser

sudo -i -u postgres psql -c "ALTER USER postgres WITH PASSWORD 'YOUR-POSTGRES-PASSWORD';"

Change YOUR-POSTGRES-PASSWORD to a secure one. The superuser is required to initialize and change the database schema for installation and updates.

Change the access policy for PostgreSQL

sudo vi /var/lib/pgsql/12/data/pg_hba.conf

Allow Horizon to access the database over the local network with an MD5 hashed password

host    all             all             127.0.0.1/32            md5(1)
host    all             all             ::1/128                 md5(1)

1	Change method from `ident` to `md5` for IPv4 and IPv6 on localhost.

Apply configuration changes for PostgreSQL

sudo systemctl reload postgresql-12

Install PostgreSQL client and server

sudo apt -y install postgresql

Create an opennms database user and password

sudo -u postgres createuser -P opennms

You must provide a password for the opennms database user. This guide uses YOUR-OPENNMS-PASSWORD as a placeholder. Please set a secure password.

Create an empty database and set the owner to the opennms user

sudo -u postgres createdb -O opennms opennms

Set a password for PostgreSQL superuser

sudo -u postgres psql -c "ALTER USER postgres WITH PASSWORD 'YOUR-POSTGRES-PASSWORD';"

Change YOUR-POSTGRES-PASSWORD to a secure one. The superuser is required to initialize and change the database schema for installation and updates.

Create a project directory for PostgreSQL and create a docker-compose.yml file

mkdir postgres
cd postgres
vi docker-compose.yml

Create the PostgreSQL service and publish the port on your local host

---
version: '3'

volumes:
  data-postgres: {}(1)

services:
  database:(2)
    image: postgres:15(3)
    container_name: database
    environment:(4)
      TZ: 'America/New_York'
      POSTGRES_USER: 'postgres'
      POSTGRES_PASSWORD: 'my-postgres-password'
    volumes:(5)
      - 'data-postgres:/var/lib/postgresql/data'
    healthcheck:(6)
      test: [ "CMD-SHELL", "pg_isready -U postgres" ]
      interval: 10s
      timeout: 3s
      retries: 3
    ports:
      - '5432:5432/tcp'

1	Persist the PostgreSQL database in a local volume.
2	PostgreSQL service is named `database` with a friendly `container_name`.
3	Image reference using the official PostgreSQL image.
4	Set the time zone and the postgres credentials for administrative tasks (for example, creating and changing database schemas for upgrades).
5	Mount the volume for persisting the PostgreSQL database files.
6	Run an internal health check to see if the PostgreSQL instance is ready.

Start the service and run it in background

docker-compose up -d

Verify the PostgreSQL process is up and running

docker-compose ps

The state should be Up (healthy) and the TCP port should be available on all interfaces

  Name                Command                 State               Ports
--------------------------------------------------------------------------------
database   docker-entrypoint.sh postgres   Up (healthy)   0.0.0.0:5432->5432/tcp

Install the core instance

For security reasons, Horizon is designed to run within an organization’s protected intranet. Do not expose the web console or sign in pages directly to the Internet without appropriate isolation controls (for example, a VPN with multi-factor authentication).

CentOS/RHEL 9
CentOS/RHEL 8
CentOS/RHEL 7
Ubuntu
Debian
Docker

Add repository and import GPG key

sudo dnf -y install https://yum.opennms.org/repofiles/opennms-repo-stable-rhel9.noarch.rpm
sudo rpm --import https://yum.opennms.org/OPENNMS-GPG-KEY

Install Horizon with all built-in dependencies

sudo dnf -y install opennms

If you want time series trending and forecast functions, you must install the R project packages. The additional download size for packages is ~390MB.

Note that R-core packages require that you have a PowerTools repository enabled.

(Optional) Install R-core packages for time series trending and forecasting

sudo dnf config-manager --set-enabled powertools
sudo dnf -y install epel-release
sudo dnf -y install R-core

Disable the OpenNMS Horizon repository after installation to prevent unwanted upgrades when upgrading other packages on the server. After upgrading, Horizon requires manual steps to upgrade configuration files or migrate database schemas to a new version. We recommend that you exclude the Horizon packages from updates except when you plan to perform an upgrade.

Disable auto updates for OpenNMS Horizon

sudo dnf config-manager --disable opennms-repo-stable-*

Verify directory structure with the tree command

sudo dnf -y install tree
tree /opt/opennms -L 1

Directory structure after successful installation

/opt/opennms
├── bin
├── contrib
├── data
├── deploy
├── etc
├── jetty-webapps
├── lib
├── logs -> /var/log/opennms
├── share -> /var/opennms
└── system

Add repository and import GPG key

sudo dnf -y install https://yum.opennms.org/repofiles/opennms-repo-stable-rhel8.noarch.rpm
sudo rpm --import https://yum.opennms.org/OPENNMS-GPG-KEY

Install Horizon with all built-in dependencies

sudo dnf -y install opennms

If you want time series trending and forecast functions you must install the R project packages. The additional download size for packages is ~390 MB.

Note that R-core packages require that you have a PowerTools repository enabled.

Install R-core packages for time series trending and forecasting (optional)

sudo dnf config-manager --set-enabled powertools
sudo dnf -y install epel-release
sudo dnf -y install R-core

Disable the OpenNMS Horizon repository after installation to prevent unwanted upgrades when upgrading other packages on the server. After upgrade, Horizon requires manual steps to upgrade configuration files or migrate database schemas to a new version. We recommend that you exclude the Horizon packages from update except when you plan to perform an upgrade.

Disable auto updates for OpenNMS Horizon

sudo dnf config-manager --disable opennms-repo-stable-*

Verify directory structure with the tree command

sudo dnf -y install tree
tree /opt/opennms -L 1

Directory structure after successful installation

/opt/opennms
├── bin
├── contrib
├── data
├── deploy
├── etc
├── jetty-webapps
├── lib
├── logs -> /var/log/opennms
├── share -> /var/opennms
└── system

Add repository and import GPG key

sudo yum -y install https://yum.opennms.org/repofiles/opennms-repo-stable-rhel7.noarch.rpm
sudo rpm --import https://yum.opennms.org/OPENNMS-GPG-KEY

Install Horizon with all built-in dependencies

sudo yum -y install opennms

If you want time series trending and forecast functions you must install the R project packages. The additional download size for packages is ~390 MB.

Note that R-core packages require that you have a PowerTools repository enabled.

Install R-core packages for time series trending and forecasting (optional)

sudo dnf config-manager --set-enabled powertools
sudo yum -y install epel-release
sudo yum -y install R-core

Disable auto updates for OpenNMS Horizon

sudo yum -y install yum-utils
sudo yum-config-manager --disable opennms-repo-stable-*

Verify directory structure with the tree command

sudo yum -y install tree
tree /opt/opennms -L 1

Directory structure after successful installation

/opt/opennms
├── bin
├── contrib
├── data
├── deploy
├── etc
├── jetty-webapps
├── lib
├── logs -> /var/log/opennms
├── share -> /var/opennms
└── system

Add OpenNMS repository GPG key

curl -fsSL https://debian.opennms.org/OPENNMS-GPG-KEY | sudo gpg --dearmor -o /usr/share/keyrings/opennms.gpg

Add and update apt repository

echo "deb [signed-by=/usr/share/keyrings/opennms.gpg] https://debian.opennms.org stable main" | sudo tee /etc/apt/sources.list.d/opennms.list
sudo apt update

You can safely ignore the message about conflicting distributions (expected stable but got opennms-xx).

Install OpenNMS Horizon with built-in dependencies (optional)

sudo apt -y install opennms

Install R packages for trending and forecasting (optional)

If you want time series trending and forecast functions you have to install the R project packages. The additional download size for packages is ~152 MB.

sudo apt -y install r-recommended

sudo apt-mark hold libopennms-java \
              libopennmsdeps-java \
              opennms-common \
              opennms-db

Verify directory structure with the tree command

sudo apt -y install tree
tree /usr/share/opennms -L 1

Directory structure after successful installation

/usr/share/opennms
├── bin
├── data
├── deploy
├── etc -> /etc/opennms
├── jetty-webapps
├── lib -> ../java/opennms
├── logs -> /var/log/opennms
├── share -> /var/lib/opennms
└── system

Install GnuPG and add OpenNMS repository GPG key

sudo apt -y install curl gnupg ca-certificates
curl -fsSL https://debian.opennms.org/OPENNMS-GPG-KEY | sudo gpg --dearmor -o /usr/share/keyrings/opennms.gpg

Add and update apt repository

echo "deb [signed-by=/usr/share/keyrings/opennms.gpg] https://debian.opennms.org stable main" | sudo tee /etc/apt/sources.list.d/opennms.list
sudo apt update

You can safely ignore the message about conflicting distributions (expected stable but got opennms-xx).

Install OpenNMS Horizon with built-in dependencies

sudo apt -y install opennms

Install R packages for trending and forecasting (optional)

If you want time series trending and forecast functions you must install the R project packages. The additional download size for packages is ~134 MB.

sudo apt -y install r-recommended

sudo apt-mark hold libopennms-java \
              libopennmsdeps-java \
              opennms-common \
              opennms-db

Verify directory structure with the tree command

sudo apt -y install tree
tree /usr/share/opennms -L 1

Directory structure after successful installation

/usr/share/opennms
├── bin
├── data
├── deploy
├── etc -> /etc/opennms
├── jetty-webapps
├── lib -> ../java/opennms
├── logs -> /var/log/opennms
├── share -> /var/lib/opennms
└── system

Create a project directory for Horizon Core and create a docker-compose.yml file.

mkdir horizon
cd horizon
vi docker-compose.yml

---
version: '3'

volumes:(1)
  data-opennms: {}
  data-config: {}

services:
  horizon:(2)
    image: opennms/horizon:33.0.10(3)
    container_name: horizon
    environment:
      TZ: 'America/New_York'(4)
      POSTGRES_HOST: 'my-database-host'(5)
      POSTGRES_PORT: 5432
      POSTGRES_USER: 'postgres'
      POSTGRES_PASSWORD: 'my-postgres-password'
      OPENNMS_DBNAME: 'opennms-core-db'
      OPENNMS_DBUSER: 'opennms'
      OPENNMS_DBPASS: 'my-opennms-db-password'
    volumes:(6)
      - data-opennms:/opennms-data
      - data-config:/opt/opennms/etc
    command: ["-s"]
    ports:(7)
      - '8980:8980/tcp'
      - '8101:8101/tcp'
    healthcheck:
      test: [ 'CMD', 'curl', '-f', '-I', 'http://localhost:8980/opennms/login.jsp' ](8)
      interval: 1m
      timeout: 5s
      retries: 3

1	Volume definitions to persist the Horizon Core data and configuration files.
2	The Horizon Core instance service is named `horizon` with a friendly `container_name`.
3	Image reference using the Horizon container image with the Core services.
4	Set the time zone and the postgres credentials to initialize the database that the Horizon Core instance uses. To list all available time zones, use `timedatectl list-timezones`.
5	Set the host or IP address of the host that runs the PostgreSQL database.
6	Mount directories to store RRD files, PDF reports, and configuration files in a persistent volume.
7	Publish ports to access the web UI and the Karaf shell.
8	Run an internal health check against the web UI to verify service health status.

The process inside the container runs as a non-privileged user with user id 10001. If you want the configuration files in a bind mount on your local host system, make sure you set permissions and ownership accordingly with chown 10001:10001 ./path/to/my/config-dir.

To run a release candidate or a different version, use the public image tags from our repository on DockerHub.

Validate your Docker Compose file

docker-compose config -q

Set up the core instance

CentOS/RHEL 7/8/9
Debian/Ubuntu
Docker

Configure PostgreSQL database access

You can store your PostgreSQL credentials in the secure credentials vault. To do this, use the scvcli command line utility to add the credentials, and reference these credentials in opennms-datasources.xml:

Create encrypted credentials for the PostgreSQL database connections:
```
sudo -u opennms ${OPENNMS_HOME}/bin/scvcli set postgres opennms password (1)
sudo -u opennms ${OPENNMS_HOME}/bin/scvcli set postgres-admin postgres password
```
1 Replace both password instances with the actual passwords for your opennms and postgres database accounts.

Edit opennms-datasources.xml with vi:

sudo -u opennms vi /opt/opennms/etc/opennms-datasources.xml

Set encrypted credentials to access the PostgreSQL database:

...
<jdbc-data-source name="opennms"
                    database-name="opennms" (1)
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/opennms" (2)
                    user-name="${scv:postgres:username}" (3)
                    password="${scv:postgres:password}" /> (4)

<jdbc-data-source name="opennms-admin"
                    database-name="template1"
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/template1" (5)
                    user-name="${scv:postgres-admin:username}" (6)
                    password="${scv:postgres-admin:password}" /> (7)
...
<jdbc-data-source name="opennms-monitor"
                    database-name="postgres"
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/postgres" (8)
                    user-name="${scv:postgres-admin:username}" (9)
                    password="${scv:postgres-admin:password}" /> (10)
...

1	Set the database name that Horizon should use.
2	Set the JDBC connection string to your Postregres server for the instance database.
3	Set the user name to access the opennms database table.
4	Set the password to access the opennms database table.
5	Set the JDBC connection string to your Postregres server for the schema database
6	Set the postgres user for administrative access to PostgreSQL.
7	Set the password for administrative access to PostgreSQL.
8	Set the JDBC connection string to your Postregres server for the system database.
9	Set the postgres user for administrative access to PostgreSQL.
10	Set the password for administrative access to PostgreSQL.

Detect and assign Java environment and persist in /opt/opennms/etc/java.conf

sudo /opt/opennms/bin/runjava -s

Initialize the database and detect system libraries persisted in /opt/opennms/etc/libraries.properties

sudo /opt/opennms/bin/install -dis

Assign CAP_NET_RAW capabilities

Horizon runs as a non-root user, which requires having a Linux kernel greater than 3.10. If you run on an older kernel and you cannot upgrade your OS, you need to assign CAP_NET_RAW capabilities:

Run systemctl edit opennms.service and add the following code to the [Service] section:
```
AmbientCapabilities=CAP_NET_RAW CAP_NET_BIND_SERVICE
```

Reload the systemd unit with systemctl daemon-reload and restart the service with systemctl restart opennms.

(For more background on this issue, see H29+ won’t start with permission error to open ICMP socket on Discourse.)

Enable Horizon core instance on system boot and start immediately

sudo systemctl enable --now opennms

Allow connection to the web UI from your network

sudo firewall-cmd --permanent --add-port=8980/tcp
sudo systemctl reload firewalld

Configure PostgreSQL database access

Create encrypted credentials for the PostgreSQL database connections:
```
sudo -u opennms ${OPENNMS_HOME}/bin/scvcli set postgres opennms password (1)
sudo -u opennms ${OPENNMS_HOME}/bin/scvcli set postgres-admin postgres password
```
1 Replace both password instances with the actual passwords for your opennms and postgres database accounts.

Edit opennms-datasources.xml with vi:

sudo -u opennms vi /usr/share/opennms/etc/opennms-datasources.xml

Set encrypted credentials to access the PostgreSQL database:

...
<jdbc-data-source name="opennms"
                    database-name="opennms" (1)
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/opennms" (2)
                    user-name="${scv:postgres:username}" (3)
                    password="${scv:postgres:password}" /> (4)

<jdbc-data-source name="opennms-admin"
                    database-name="template1"
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/template1" (5)
                    user-name="${scv:postgres-admin:username}" (6)
                    password="${scv:postgres-admin:password}" /> (7)
...
<jdbc-data-source name="opennms-monitor"
                    database-name="postgres"
                    class-name="org.postgresql.Driver"
                    url="jdbc:postgresql://localhost:5432/postgres" (8)
                    user-name="${scv:postgres-admin:username}" (9)
                    password="${scv:postgres-admin:password}" /> (10)
...

1	Set the database name that Horizon should use.
2	Set the JDBC connection string to your Postregres server for the instance database.
3	Set the user name to access the opennms database table.
4	Set the password to access the opennms database table.
5	Set the JDBC connection string to your Postregres server for the schema database
6	Set the postgres user for administrative access to PostgreSQL.
7	Set the password for administrative access to PostgreSQL.
8	Set the JDBC connection string to your Postregres server for the system database.
9	Set the postgres user for administrative access to PostgreSQL.
10	Set the password for administrative access to PostgreSQL.

Detect Java environment and persist in /usr/share/opennms/etc/java.conf

sudo /usr/share/opennms/bin/runjava -s

Initialize the database and detect system libraries persisted in /opt/opennms/etc/libraries.properties

sudo /usr/share/opennms/bin/install -dis

Binding to privileged ports

The core service user must be able to send ICMP echo requests. During setup, the permissions for net.ipv4.ping_group_range are set permanently on boot via /etc/sysctl.d/99-opennms-non-root-icmp.conf. Some system kernels do not honor this setting; in those cases, additional configuration is required to allow binding to privileged ports. We recommend creating a systemd overlay to add the necessary settings to the service configuration:

Run systemctl edit opennms.service and add the following line to the [Service] section:
```
AmbientCapabilities=CAP_NET_RAW CAP_NET_BIND_SERVICE
```

Reload the systemd unit with systemctl daemon-reload and restart the service with systemctl restart opennms.

(For more background on this issue, see H29+ won’t start with permission error to open ICMP socket on Discourse.)

Enable Horizon core instance on system boot and start immediately

sudo systemctl enable --now opennms

Allow connection to the web UI from your network

If you are using Uncomplicated Firewall (UFW) as your host firewall, you can allow access to the web user interface with the command:

sudo ufw allow 8980/tcp

Prepare a local configuration directory to run as an unprivileged user

mkdir etc
chown 10001:10001 -R etc

Initialize the database and schema and a configuration directory

docker-compose run horizon -i

Start service in background

docker-compose up -d

You can also use this command when you run upgrades. You must delete the file etc/configured file first. It works as a guard to prevent unnecessary database migration runs on startup.

Show configuration changes from a pristine system with
docker-compose exec -w /opt/opennms/bin horizon ./config-diff.sh -d.

If you changed your configuration files manually you can run the configuration tester with
docker-compose exec horizon bin/config-tester -a

First-time sign in

After you start the Horizon core services, you can access the web application at http://core-instance-ip:8980/opennms. The default user credentials are as follows:

Username: admin
Password: admin

When you try to sign in with these credentials, Horizon prompts you to change your password. Although you also have the option to skip this action and sign in with default the credentials, we strongly recommend that you change the admin account’s password to a secure one.

Type your current password.
Type your new password and confirm it.
Click Change Password.

To change your account’s password after the first time you sign in, follow these steps:

On the top menu bar, click Admin Change Password.
Type your current password and new password in the appropriate fields.
Confirm your new password, and click Submit.

The password is updated.

We encourage you to use Horizon with individual user accounts instead of using only the admin account. If all users have individual accounts, you can see who is completing tasks (for example, clearing or acknowledging alarms). For information on how to create personalized user accounts, see Create a new user in the Quick Start guide.

Usage statistics

The first time you sign in, Horizon notifies you that it collects anonymized usage statistics and publishes them to https://stats.opennms.com. Consent to share collected usage statistics is assumed by default.

The OpenNMS Group uses this information to help determine product use and to improve the Horizon software. We do not share it with third parties, and we will not use it for sales purposes.

Click Learn More to view the information that we collect and share. This also hides the notification.

Click Dismiss to simply hide the notification. You can view the usage statistics at any time on the admin page.

Admin users can opt out of sharing the statistics at any time.

First monitored node

The default configuration will discover a single node with an interface 127.0.0.1 and detect services exposed on the loopback interface, including the OpenNMS-JVM service. Nodes with this service have JMX-based data collection performed on Java JVM statistics such as heap memory and open file handles.

Next steps

See the Quick Start guide for more information on setting up and configuring your Horizon instance.

Installation and Configuration

DNS considerations

Quick installation

Scope

Requirements

Set up PostgreSQL

Pool size and maximum database connections

Install the core instance

Set up the core instance

First-time sign in

Change password after first sign in

Usage statistics

First monitored node

Related topics

Next steps