Enable systemd_timesyncd Service

This page is not yet available in Spanish. We are working on its translation.
If you have any questions or feedback about our current translation project, feel free to reach out to us!

Description

The systemd_timesyncd service can be enabled with the following command:

$ sudo systemctl enable systemd_timesyncd.service

Rationale

Enabling the systemd_timesyncd service ensures that this host uses the ntp protocol to fetch time data from a ntp server. Synchronizing time is essential for authentication services such as Kerberos, but it is also important for maintaining accurate logs and auditing possible security breaches.

Additional information on Ubuntu network time protocol is available at https://help.ubuntu.com/lts/serverguide/NTP.html.en.

Remediation

Shell script

The following script can be run on the host to remediate the issue.

#!/bin/bash

# Remediation is applicable only in certain platforms
if dpkg-query --show --showformat='${db:Status-Status}
' 'kernel' 2>/dev/null | grep -q installed && { ( ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'chrony' 2>/dev/null | grep -q installed ) && ! ( dpkg-query --show --showformat='${db:Status-Status}\n' 'ntp' 2>/dev/null | grep -q installed ) ); }; then

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" unmask 'systemd-timesyncd.service'
"$SYSTEMCTL_EXEC" start 'systemd-timesyncd.service'
"$SYSTEMCTL_EXEC" enable 'systemd-timesyncd.service'

else
    >&2 echo 'Remediation is not applicable, nothing was done'
fi

Ansible playbook

The following playbook can be run with Ansible to remediate the issue.

- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.1
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_timesyncd_enabled

- name: Enable systemd_timesyncd Service - Enable service systemd-timesyncd
  block:

  - name: Gather the package facts
    package_facts:
      manager: auto

  - name: Enable systemd_timesyncd Service - Enable Service systemd-timesyncd
    ansible.builtin.systemd:
      name: systemd-timesyncd
      enabled: true
      state: started
      masked: false
    when:
    - '"systemd" in ansible_facts.packages'
  when:
  - '"kernel" in ansible_facts.packages'
  - ( not ( "chrony" in ansible_facts.packages ) and not ( "ntp" in ansible_facts.packages
    ) )
  tags:
  - NIST-800-53-AU-8(1)(a)
  - NIST-800-53-CM-6(a)
  - PCI-DSS-Req-10.4
  - PCI-DSSv4-10.6
  - PCI-DSSv4-10.6.1
  - enable_strategy
  - high_severity
  - low_complexity
  - low_disruption
  - no_reboot_needed
  - service_timesyncd_enabled