I am using duplicity 0.7.05 to periodically backup a directory that resides on a Linux system, using a GnuPG key pair with an encrypted private key. Since the public key is not encrypted, the passphrase is not required for the backup process, but it is required for accessing the backups.
I would now like to automatically delete old backups using the
remove-all-inc-of-but-n-full duplicity options. To my surprise, duplicity will ask for the GnuPG passphrase when removing old backups, which makes it impossible to do so automatically.
Why does duplicity ask for the GnuPG passphrase in this case? It seems to me that it should not need to access the backup contents just to figure out which backup file sets to remove.