#Nexus Migration Guide: 3.69.0 to 3.76.0 (Alauda Build of Nexus Operator Version v3.76.z)

#Overview

This document provides detailed instructions for migrating Nexus Repository Manager from version 3.69.0 to 3.76.0. Due to Nexus discontinuing OrientDB support after version 3.70, a manual data migration process is required.

#Prerequisites

• Install Alauda Build of Nexus Operator v3.76.z version
• Ensure sufficient system resources are available for the upgrade
• Use product functionality to upgrade Nexus to version 3.69.0

#Migration Process

#1. Data Backup

Create backup directory (ensure sufficient local disk space for backup):

mkdir -p nexus-backup

Set environment variables:

export INSTANCE_NAME=<nexus instance name> 
export INSTANCE_NAMESPACE=<nexus instance namespace>
export POD_NAME=$(kubectl -n ${INSTANCE_NAMESPACE} get pod -l release=${INSTANCE_NAME} | grep ${INSTANCE_NAME} | awk '{print $1}')

#1.1 Service Shutdown

Before deletion, you must uninstall the old version operator first, otherwise the service will be automatically recreated after deletion.

kubectl -n ${INSTANCE_NAMESPACE} delete service -l release=${INSTANCE_NAME}

#1.2 Backup Blob Storage

mkdir -p nexus-backup/blobs
kubectl -n ${INSTANCE_NAMESPACE} cp ${POD_NAME}:/nexus-data/blobs nexus-backup/blobs

#1.3 Database Backup

1. Navigate to: Admin Dashboard > System > Tasks
2. Create new task:
   • Type: Admin - Export databases for backup
   • Task name: [Your choice]
   • Backup location: [Specify path] - The directory path must be within the Nexus data volume directory.
   • Frequency: Manual
3. Execute task and verify completion status

#2. Database Migration

#2.1 OrientDB to H2 Conversion

Set environment variables:

export INSTANCE_NAME=<old nexus instance name> 
export INSTANCE_NAMESPACE=<old nexus instance namespace>
export POD_NAME=$(kubectl -n ${INSTANCE_NAMESPACE} get pod -l release=${INSTANCE_NAME} | grep ${INSTANCE_NAME} | awk '{print $1}')

Access container and download migration tool:

kubectl -n ${INSTANCE_NAMESPACE} exec -it ${POD_NAME} -- bash
cd /nexus-data/backup
wget https://download.sonatype.com/nexus/nxrm3-migrator/nexus-db-migrator-3.70.3-01.jar -O nexus-db-migrator.jar

If direct network download is not available, you can download the file locally first and then copy it to the container:

kubectl -n ${INSTANCE_NAMESPACE} cp nexus-db-migrator.jar ${POD_NAME}:/nexus-data/backup

Execute migration:

# The nexus.mv.db file will be generated in the backup directory, indicating migration completion
java -Xmx16G -Xms16G -XX:+UseG1GC -XX:MaxDirectMemorySize=28672M -jar nexus-db-migrator.jar --migration_type=h2

Backup converted database:

kubectl -n ${INSTANCE_NAMESPACE} cp ${POD_NAME}:/nexus-data/backup/nexus.mv.db nexus-backup/nexus.mv.db

#3. New Instance Deployment

Since data and storage are imported from the original instance, when deploying the new instance, you only need to maintain the same access method as the original instance.

Note: Using the same NodePort and Ingress configuration as the old version will cause conflicts and prevent creation. Configure new values instead, and after successful migration, delete the old version instance and then modify the external exposure settings.

#3.1 Configuration Options

For NodePort access:

helmValues:
   service:
     nexus:
       enabled: true
       nodePort: <port>

For HTTP ingress:

service:
  nexus:
    enabled: true
    type: ClusterIP

ingress:
  enabled: true
  host: <domain>
  defaultRule: true

For HTTPS ingress:

helmValues:
   service:
     nexus:
       enabled: true
       type: ClusterIP
   
   ingress:
     enabled: true
     host: <domain>
     defaultRule: true
     tls:
       - secretName: <tls-secret>
         hosts:
         - <domain>

#3.2 Data Import

Set new instance variables:

export INSTANCE_NAME=<new nexus instance name> 
export INSTANCE_NAMESPACE=<new nexus instance namespace>
export POD_NAME=$(kubectl -n ${INSTANCE_NAMESPACE} get pod -l app.kubernetes.io/instance=${INSTANCE_NAME} | grep ${INSTANCE_NAME} | awk '{print $1}')

Clear existing data (skip this step if the new data volume is empty):

kubectl -n ${INSTANCE_NAMESPACE} exec -it ${POD_NAME} -- rm -rf /nexus-data/blobs /nexus-data/db/nexus.mv.db 

Import backup data:

kubectl -n ${INSTANCE_NAMESPACE} cp nexus-backup/blobs ${POD_NAME}:/nexus-data
kubectl -n ${INSTANCE_NAMESPACE} cp nexus-backup/nexus.mv.db ${POD_NAME}:/nexus-data/db

Then restart the Nexus Pod.

#4. Verification Steps

1. Verify pod status:

   kubectl -n ${INSTANCE_NAMESPACE} get pods -l app.kubernetes.io/instance=${INSTANCE_NAME}

2. Validation checklist:

   • Web UI accessibility
   • Repository visibility
   • Artifact upload functionality
   • Artifact download functionality
   • User authentication
   • Repository permissions

3. Post-migration cleanup:

   • Remove old instance after successful verification (requires reinstalling the old version operator to complete old instance resource cleanup)
   • Archive backups according to retention policy