Database Options

We highly recommend that you have your Nexus Repository 3 instance use an external PostgreSQL database. See our documentation on configuring Nexus Repository Pro for an external PostgreSQL database or on migrating an existing Nexus Repository 3 instance to a PostgreSQL database.

Database Options for Nexus Repository

Nexus Repository has a few database options:

An external PostgreSQL database (Preferred) PRO
An embedded H2 database PRO
An embedded OrientDB database

This topic will explain the database options and benefits to an external database.

Choosing a Database Mode

We recommend that all new and existing Nexus Repository Pro deployments use PostgreSQL or H2. Using PostgreSQL will help organizations meet their resiliency, scaling, and business continuity requirements. PostgreSQL should be used for any centralized repository which require fault tolerant deployments.

The table below can help you choose the appropriate database mode for your deployment:

Database Mode	Appropriate For
External PostgreSQL (Preferred) PRO	Moderate or large workloads Enterprise deployments Mission-critical deployments of any size Cloud deployments (AWS, Azure) Deployments planning to use a resiliency deployment model Dynamic backups for a shorter maintaince window
Embedded H2 PRO	Smaller workloads (supported workload limitation is 20K requests per day and 100K components) Single-team deployments Non-mission-critical deployments Disposable deployments (e.g., temporary proxies)
Embedded OrientDB	Deployments that require formats not yet available in the new database modes Existing deployments that are not ready to migrate Repository OSS deployments For smaller workloads; for workloads over 20K requests per day and 100K components, use PostgreSQL and Nexus Repository Pro

Benefits of an External Database

There are a number of benefits to using an external database:

Easier to scale deployment; PostgreSQL will be required for planned HA functionality
Leverage managed, fault-tolerant cloud databases: AWS Aurora, RDS, Azure, etc.
Improved container orchestration such as Kubernetes and OpenShift
Fully available during backups
Support for multi-AZ cloud deployment models
Simpler and easier disaster recovery

Embedded Mode for Nexus Repository

Nexus Repository provides an embedded-database mode with improved speed using H2 instead of OrientDB. This mode is appropriate for the following scenarios:

Teams and smaller organizations with non-mission-critical Nexus Repository needs
Automatically provisioned, disposable Nexus Repository instances (e.g., pools of proxy-only instances used to shield a primary instance from a heavy read load)

Migration Information

If you are considering moving from OrientDB to H2 or PostgreSQL, read the following to stand up or migrate your instance:

Configuring Nexus Repository Pro for H2 or PostgreSQL (for new instances)
Migrating to a New Database (for migrating existing instances)

Unsupported formats will not be migrated; you will not be able to add new formats that your new database does not support. Review Feature Availability for PostgreSQL and H2 Databases and ensure that your new database supports all of your formats before attemping the migration.
Migration is a one-time process; attempts to migrate again will overwrite data.

Database Options