Note: Before upgrading, back up "<work-directory>/conf" and "<work-directory>/db". If you need to downgrade for some reason, shut down the new server, restore the "conf" and "db" directory, and start up the old Nexus.
Since Nexus separates its configuration and data storage from the application, it is easy to upgrade an existing Nexus installation. To upgrade Nexus, unpack the Nexus archive in the directory which contains the existing Nexus installation. Once the archive is unpacked, the new Nexus application directory should be a sibling to your existing sonatype-work directory. If you have defined a symbolic link for the version of Nexus to use, change that to point at the new Nexus application directory. When you start the new instance of Nexus it will read the existing repository configuration from the <work-directory>.
Note that if you have made any changes to the following files in the nexus application directory you will need to manually make the same changes in the new version, we do not support copying these files from one version to another:
Running as a Service
If you have been running Nexus as a service be sure to make sure the service is pointing to the new instance.
If you are running Nexus on Windows as a service you need to uninstall the old service and install the service from the new instance.
Migrating Nexus to/from a different Operating System
Normally all storage paths use by Nexus are caluclated automatically.
Nexus does provide an admin the option to explicitly override some paths, most commonly the storage locations of repositories. If these paths are explicitly set by an admin, then they will cause problems when migrating to an operating system that has a different directory structure, like when moving from Windows to Linux.
You should carefully examine your nexus configuration files under
sonatype-work/nexus/conf prior to OS migration and either remove or change these explicit paths to a suitable location matching the file system of the target system.
Upgrading from the Trial Edition of Nexus Professional
The procedure for upgrading from the trial edition of Nexus Professional is the same as any other upgrade. Download the latest version of Nexus Professional, and follow the standard installation instructions. When configuring the location of the nexus work directory use the one from your trial if you wish to preserve your existing configuration.