cis-ubuntu1804-v220-5-1-1-3

DevOps & Security

Ensure journald is configured to compress large log files

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5.1.1.3 Ensure journald is configured to compress large log files (Automated)

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.

Rationale

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

Audit Procedure

Command Line

Run the following command to verify that large files will be compressed:

grep -Psi '^\h*Compress\h*=\h*yes\b' /etc/systemd/journald.conf /etc/systemd/journald.conf.d/*

Verify the output matches:

Compress=yes

Expected Result

The output should include Compress=yes.

Remediation

Command Line

Edit the /etc/systemd/journald.conf file or a file ending in .conf in /etc/systemd/journald.conf.d/ and add the following line:

Compress=yes

Restart the service:

systemctl restart systemd-journald

Default Value

Compress=yes

References

NIST SP 800-53 Rev. 5: AU-4

CIS Controls

Controls Version	Control
v8	8.2 Collect Audit Logs - Collect audit logs. Ensure that logging, per the enterprise's audit log management process, has been enabled across enterprise assets.
v8	8.3 Ensure Adequate Audit Log Storage - Ensure that logging destinations maintain adequate storage to comply with the enterprise's audit log management process.
v7	6.2 Activate audit logging - Ensure that local logging has been enabled on all systems and networking devices.
v7	6.3 Enable Detailed Logging - Enable system logging to include detailed information such as an event source, date, user, timestamp, source addresses, destination addresses, and other useful elements.
v7	6.4 Ensure adequate storage for logs - Ensure that all systems that store logs have adequate storage space for the logs generated.