I am using plone.app.blob to store large ZODB objects in a blobstorage directory. This reduces size pressure on Data.fs but I have not been able to find any advice on backing up this data.
I am already backing up Data.fs by pointing a network backup tool at a directory of repozo backups. Should I simply point that tool at the blobstorage directory to backup my blobs?
What if the database is being repacked or blobs are being added and deleted while the copy is taking place? Are there files in the blobstorage directory that must be copied over in a certain order?
Backing up "blobstorage" will do it. No need for a special order or anything else, it's very simple.
All operations in Plone are fully transactional, so hitting the backup in the middle of a transaction should work just fine. This is why you can do live backups of the ZODB. Without knowing what file system you're on, I'd guess that it should work as intended.