2.2.1.1 Ensure time synchronization is in use (Not Scored)

Level 1 - Server 
Level 1 - Workstation

System time should be synchronized between all systems in an environment. This is typically done by establishing an authoritative time server or set of servers and having all systems synchronize their clocks to them.

Time synchronization is important to support time sensitive security mechanisms like Kerberos and also ensures log files have consistent time records across the enterprise, which aids in forensic investigations.

On physical systems or virtual systems where host based time synchronization is not available run the following commands and verify either NTP or chrony is installed:

# rpm -q ntp 
# rpm -q chrony

On virtual systems where host based time synchronization is available consult your virtualization software documentation and verify that host based synchronization is in use.

On physical systems or virtual systems where host based time synchronization is not available install NTP or chrony using one of the following commands:

# yum install ntp 
# yum install chrony

On virtual systems where host based time synchronization is available consult your virtualization software documentation and setup host based synchronization.