Geo: Document Using the New Container Registry Metadata Database
Problem to solve
What product or feature(s) affected?
Category:Geo Replication
Category:Container Registry
What docs or doc section affected?
https://docs.gitlab.com/ee/administration/geo/replication/container_registry.html
Is there a problem with a specific document, or a feature/process that's not addressed sufficiently in docs?
The current Geo documentation for container registry does not address the new metadata database, which is currently being rolled out to self-managed: Release container registry with metadata databa... (&5521)
Further details
This documentation should address:
- setting up a secondary site for a primary site which is already using the registry metadata database
- migrating both sides of an existing geo site to the new registry database
- general setup guidelines
Impact
Enable geo-distributed GitLab deployments to use the new container registry metadata database, ensuring consistent replication across sites while maintaining data integrity.
Proposal
Setting up a secondary site for a primary site which is already using the registry metadata database
All that needs to be done in this instance is for the new secondary site to come up with the database already enabled. The key here is to avoid syncing from a primary using the database to a secondary, which is not because database backed registries have more API endpoints than object storage metadata registries and therefore cannot be synced in this direction.
Migrating an Existing Geo deployment
This would require breaking replication, and migrating each site independently before reconnecting them. Migration documentation can be found for charts and omnibus
General Setup Guidelines
For the container registry database, there needs to be a 1:1 relationship between databases and backend object storage for registry blobs. If each site has its own object storage for registry, each site needs a separate database. If each site uses the same object storage for both registries, then there should be a single database for that object storage.
Who can address the issue
The expertise required for this is both Geo and container registry.