Installing Nexus Repository Pro with a PostgreSQL Database

This topic covers installing Sonatype Nexus Repository with an external PostgreSQL database; note that using an external PostgreSQL database requires a paid Pro license.

Sonatype Nexus Repository's legacy embedded OrientDB database entered extended maintenance in August 2024. All Sonatype Nexus Repository customers are highly encouraged to migrate off of OrientDB.

Users that cannot migrate need to remain on the 3.70.x version line. Nexus Repository versions 3.71.0 and above will not support OrientDB.

New installations of Nexus Repository version 3.71.0 and above default to using an embedded H2 database.

Data Store Configuration View to Determine Current Database

Use the Data Store view to determine the database model Nexus Repository is using.

Instances using H2 will see a reference to H2 in their JDBC URL.
Instances using PostgreSQL will not see a reference to H2 in the JDBC URL.

Best Practices

Nexus Repository supports 3 methods for providing the database configuration settings: as environment variables, as JVM arguments, or in the properties file.

When Nexus Repository starts, the first connection method encountered is used while the others are ignored. Mixing methods are not supported.
Choose the method that fits your infrastructure requirements. In containerized environments, use environment variables or JVM arguments to avoid modifying the property files in the container.
Any new configuration settings take effect on restart of the Nexus Repository service.

Installation Instructions

The following instructions are to start Nexus Repository using an external PostgreSQL database.

Before proceeding, ensure you meet the PostgreSQL requirements in the system requirements with the required trigram module installed.
Download the latest Sonatype Nexus Repository version; expand and install the archive.
Create a PostgreSQL database using the UTF8 character set for compatibility with Nexus Repository.
For more information, see the PostgreSQL documentation on setting the character set.
Modify the <data-dir>/etc/nexus.properties file with the following properties.
```
nexus.licenseFile=/path/to/your/sonatype-license.lic
```
The license file is only needed and used for the initial run; after which the value is managed in the database.
The connection configuration is set using any of the following 3 different methods.
1. Pass the connectivity details as environment variables:
```
NEXUS_DATASTORE_NEXUS_JDBCURL
NEXUS_DATASTORE_NEXUS_USERNAME
NEXUS_DATASTORE_NEXUS_PASSWORD
```
2. Specify the properties as JVM arguments:
```
-Dnexus.datastore.enabled
-Dnexus.datastore.nexus.username
-Dnexus.datastore.nexus.password
-Dnexus.datastore.nexus.jdbcUrl
```
3. Create the <data-dir>/etc/fabric/nexus-store.properties directory and file with your PostgreSQL configuration.
```
username=<postgres_user>
password=<postgres_password>
jdbcUrl=jdbc\:postgresql\://<database-host>\:<database-port>/<database-name>
```
  Colons in the JDBC URL need to be escaped with a backslash (\). For AWS Aurora databases, include the gssEncMode=disable query parameter in the JDBC URL
Start the Nexus Repository instance using a PostgreSQL database.

Configuration Options for PostgreSQL

Set optional configuration settings through the same methods used above. Set multiple advanced properties in the JVM arguments by delimiting the values with "\n".

advanced=maximumPoolSize\=200\nmaxLifetime\=840000

Maximum Pool Size

Servers under heavy load may need increased connection pool size for the database. Nexus Repository uses a default pool of 100.

Note

Note that, for high availability deployments, you must increase the number of connections that PostgreSQL allows so that your Maximum Connection Pool size does not exceed your the maximum number of allowed connections. See Prerequisite Step: Adjust max_connections.

Pass an environment variable

NEXUS_DATASTORE_NEXUS_ADVANCED="maximumPoolSize=200"

Use a JVM argument

-Dnexus.datastore.nexus.advanced=maximumPoolSize\=200

In the nexus-store.properties file
```
maximumPoolSize=N
advanced=maximumPoolSize\=200
```
Only one setting from above is used. The maximumPoolSize takes precedence over the advanced

Max Lifetime

Configure the max lifetime for database connections when using container orchestration tools, relational database services, or other infrastructure to launch Nexus Repository.

The default max lifetime is set to 30 minutes (1800000ms)
Set the max lifetime to be several seconds shorter than any infrastructure-imposed connection time limit.

Pass as an environment variable

NEXUS_DATASTORE_NEXUS_ADVANCED="maxLifetime=840000"