Cis Ubuntu2004 V300 2 3 3 3

Ensure chrony is enabled and running

Profile

• Level 1 - Server
• Level 1 - Workstation

Description

chrony is a daemon which implements the Network Time Protocol (NTP) and is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate.

chrony can be configured to be a client and/or a server.

More information on chrony can be found at: http://chrony.tuxfamily.org/.

Note:

• If systemd-timesyncd is being used, chrony should be removed and this section skipped
• Only one time synchronization method should be in use on the system

Audit

• IF - chrony is in use on the system, run the following commands:

Run the following command to verify chrony is enabled:

Command Line

# systemctl is-enabled chrony.service

Output:

enabled

Run the following command to verify chrony is running:

# systemctl is-active chrony.service

Output:

active

Remediation

• IF - chrony is in use on the system, run the following commands:

Run the following command to unmask chrony.service:

Command Line

# systemctl unmask chrony.service

Run the following command to enable and start chrony.service:

# systemctl --now enable chrony.service

- OR -

If another time synchronization service is in use on the system, run the following command to remove chrony from the system:

# apt purge chrony
# apt autoremove chrony

References

1. NIST SP 800-53 Rev. 5: AU-8

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