I wonder is there's an inbuilt way in azure to backup a blob account, or just a container if that can't be done. Looked into azure backup service but can't find the option for doing it, just options to backup VM.
Alternatively I can write my custom back up strategy, but not sure if it's the case that I can't find that option inbuilt.
Thanks,
There is no blob backup facility. You'll need to make your own backups (e.g. making copies of blobs, either to the same storage account or a different one). You can take snapshots, but as @Gaurav points out in comments, snapshots are tied to the original blob, so if you delete the original, you delete the snapshots.
I answered a similar question regarding backups and Table Storage, as well, here.
