To simulate installing updates, do not actually do it
$ sudo unattended-upgrade --dry-run
To print debug messages
$ sudo unattended-upgrade -d
To make apt/libapt print verbose debug messages
$ sudo unattended-upgrade --apt-debug -v
To print info messages
$ sudo unattended-upgrade -v
To make Only download, do not even try to install
$ sudo unattended-upgrade --download-only
To make upgrade in minimal steps
$ sudo unattended-upgrade --minimal-upgrade-steps
To upgrade all packages together instead of in smaller sets
$ sudo unattended-upgrade --no-minimal-upgrade-steps
To show this help message
$ sudo unattended-upgrade -h
regards,
T.Dhanasekar