# run `apt-get upgrade` on all waeup hosts

## use this if you are sure there are no problems ahead (adventurous)
# ansible -i hosts all -K -b -m shell -a "/usr/bin/aptitude -y safe-upgrade"
## use this version to abort in any complex situation (safe way)
ansible -i hosts all -K -b -m shell -a "/usr/bin/apt-get -y --trivial-only upgrade"