I had a lot of help over at this thread
to set up incremental backups with crontab. I just discovered that tar is not actually incrementing the tar files. I first created the tar files, then in crontab I have:
cd /; tar -cpf --incremental --exclude-from=/root/ExcludeFromTar.txt mnt/PATRIOT/bkp/home.tar home
I only just discovered that this creates a file whose filename is "/--incremental". I also tried using tar's -G switch instead of --incremental:
cd /; tar -cpfG --exclude-from=/root/ExcludeFromTar.txt mnt/PATRIOT/bkp/home.tar home
but this creates a file whose filename is "/G". The contents of /--incremental and /G are my home directory, but why is the target file not being updated? This is the symptom of mistaken syntax in the tar command, but I don't see what's wrong in the command I posted above. What am I missing?