Instead of copying all the media library files from the production environment, for large media libraries of millions of files and hundreds of gigabytes of data could take many hours, VIP Go provides a service called UnionFS.
UnionFS works by making the files for the production site available to all non-production sites in read-only mode. Files shared by UnionFS in this way are served from the same infrastructure and have the same caching rules applied.
The non-production environment can upload a file of the same name to the same URL, and this will override the file shown on the non-production site (the production file remains untouched).
- The non-production environment cannot delete a file on the production site. The operation will not error, but the production file will still be shared and available from the non-production environment.
- If the file is deleted from production, it will no longer be available to be shared with the non-production environments.