# Upgrade all the Ubuntu servers.
ansible ubuntu_18_servers,ubuntu_16_servers,k8s_servers] -m apt -a "upgrade=yes update_cache=yes" -b

# Upgrade all the Ubuntu servers.
ansible debian -m apt -a "upgrade=yes update_cache=yes" -b

# Upgrade all the CentOS servers.
ansible centos_7_servers -m yum -a "name=* state=latest" -b

# Upgrade all the Fedora servers.
ansible fedora -m dnf -a "name=* state=latest" -b