Guidance on Upgrading to H2 database

Sonatype Nexus Repository
1

Hello,

We are planning to migrate from OrientDB to the H2 database, and I have been reviewing the following documentation:

Upgrading to 3.71.0+ for Instances Using OrientDB, Nexus Repository 3.70.x, and Java 8 or 11

I would like to clarify the following points:

  1. My Nexus data is approximately 100GB (including artifacts, Docker images, etc.). When we run the backup task as described in the documentation, we are instructed to copy the backup files to a clean working directory.
  2. What will the size of the backup be? Will there be any compression, or will the backup size be the same as the original data?

I have not yet set up the development environment to test this, but I wanted to confirm the backup size so that I can include it in the prerequisites for the migration.

Additionally, I am hosting Nexus in a container and will be performing the migration from OrientDB to H2.

Thank you in advance for your help!

SAM

2

Hello,
you only need to backup the database, not the whole repository data.
The database is much smaller than the whole repository - you can check the current size of your db directory to find out its size.

The database backup would be likely smaller than that (in our case it was approx. 50% of the Orient db directory size, but expect the difference to be smaller for large instances).

And the migrated H2 database file could be even smaller than the backup (in our case it was approx. 20% of the Orient db directory size, but again expect the difference to be smaller for large instances).

If you’re running the Nexus at a virtual machine, simply attach some temporary virtual disk to it and test the whole database backup and migration there. You can even do it without impacting the running Nexus instance this way.

1 Like
3

Thank you , I will test and confirm