1.2.20 Ensure that the --audit-log-maxbackup argument is set to 10 or as appropriate

[scfast]

Profile Applicability:
• Level 1 - Master Node

Description:
Retain 10 or an appropriate number of old log files.

Rationale:
Kubernetes automatically rotates the log files. Retaining old log files ensures that you
would have sufficient log data available for carrying out any investigation or correlation.
For example, if you have set file size of 100 MB and the number of old log files to keep
as 10, you would approximate have 1 GB of log data that you could potentially use for
your analysis.

Impact:
None

Audit:
Run the following command on the Control Plane node:
ps -ef | grep kube-apiserver
Verify that the --audit-log-maxbackup argument is set to 10 or as appropriate.

Default Value:
By default, auditing is not enabled.

References:

1. https://kubernetes.io/docs/admin/kube-apiserver/
2. https://kubernetes.io/docs/concepts/cluster-administration/audit/
3. API Audit Logging kubernetes/enhancements#22