cis-ubuntu1604-v200-4-2-2-2

DevOps & Security

Ensure journald is configured to compress large log files

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_16.04_LTS_Benchmark_v2.0.0/cis-ubuntu1604-v200-4-2-2-2/SKILL.md

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CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 4.2.2.2

Profile

Level: 1 - Server
Level: 1 - Workstation
Assessment Status: Automated

Description

The journald system includes the capability of compressing overly large files to avoid filling up the system with logs or making the logs unmanageably large.

Note: The main configuration file /etc/systemd/journald.conf is read before any of the custom *.conf files. If there are custom configs present, they override the main configuration parameters.

Rationale

Uncompressed large files may unexpectedly fill a filesystem leading to resource unavailability. Compressing logs prior to write can prevent sudden, unexpected filesystem impacts.

Impact

None.

Audit Procedure

Review /etc/systemd/journald.conf and verify that large files will be compressed:

Command Line

grep -e Compress /etc/systemd/journald.conf

Expected Result

Compress=yes

Remediation

Edit the /etc/systemd/journald.conf file and add the following line:

Command Line

# Add or update the following in /etc/systemd/journald.conf:
Compress=yes

Default Value

Compress is not explicitly set by default but journald defaults to compressing logs.

References

https://github.com/konstruktoid/hardening/blob/master/systemd.adoc#etcsystemdjournaldconf

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v7	6.4 Ensure adequate storage for logsEnsure that all systems that store logs have adequate storage space for the logs generated.