Information
The /etc/hosts.allow file supports access control by IP and helps ensure that only authorized systems can connect to the system.
Solution
Run the following command to create /etc/hosts.allow: # echo 'ALL: <net>/<mask>, <net>/<mask>, ...' >/etc/hosts.allow where each <net>/<mask> combination (for example, '192.168.1.0/255.255.255.0') represents one network block in use by your organization that requires access to this system.