Upgrading from Nexus 2.14.8 and beyond to Nexus 3

Before upgrading to Nexus 3, upgrade the source version to the latest Nexus 2.x version available as detailed in Upgrading from Nexus 2.x to the latest Nexus 2.x version available. Talend also recommends that you check for any platform compatibility changes between version 2.x and version 3 that may affect your deployment, for example, changes to the Java runtime environment.

For more information, see Sonatype's documentation: https://help.sonatype.com/repomanager3/upgrading.