cis-gcp-cos-2-1-1-2

name	cis-gcp-cos-2.1.1.2
description	Ensure chrony is configured
category	cis-gcp-cos
version	1.2.0
author	cyberstrike-official
tags	["cis","gcp","container-optimized-os","time-synchronization","chrony","ntp","services"]
cis_id	2.1.1.2
cis_benchmark	CIS Google Container-Optimized OS Benchmark v1.2.0
tech_stack	["gcp","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

2.1.1.2 Ensure chrony is configured (Automated)

Description

chrony is a daemon which implements the Network Time Protocol (NTP) is designed to synchronize system clocks across a variety of systems and use a source that is highly accurate. More information on chrony can be found at http://chrony.tuxfamily.org/. chrony can be configured to be a client and/or a server.

Rationale

If chrony is in use on the system proper configuration is vital to ensuring time synchronization is working properly.

This recommendation only applies if chrony is in use on the system.

Audit Procedure

Run the following command and verify remote server is configured properly:

# grep -E "^(server|pool)" /etc/chrony/chrony.conf
server <remote-server>

Multiple servers may be configured.

Run the following command and verify the first field for the chronyd process is ntp or chrony:

# ps -ef | grep chronyd
ntp       491     1  0 20:32 ?        00:00:00 /usr/sbin/chronyd

Or

# ps -ef | grep chronyd
chrony    491     1  0 20:32 ?        00:00:00 /usr/sbin/chronyd

Expected Result

The grep command should return a configured server or pool entry. The ps command should show chronyd running under the ntp or chrony user.

Remediation

Update to an OS image that has the correct chrony configuration.

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	8.4 Standardize Time Synchronization - Standardize time synchronization. Configure at least two synchronized time sources across enterprise assets, where supported.		X	X
v7	6.1 Utilize Three Synchronized Time Sources - Use at least three synchronized time sources from which all servers and network devices retrieve time information on a regular basis so that timestamps in logs are consistent.		X	X