Verify NixOS notifies the SA and ISSO (at a minimum) when allocated audit record storage volume reaches 75 percent of the repository maximum audit record storage capacity with the following command: $ sudo grep -w space_left_action /etc/audit/auditd.conf space_left_action = syslog If the "space_left_action" parameter is missing, commented out, or set to blanks, this is a finding. If the "space_left_action" is set to "syslog", the system logs the event, but does not generate a notification, this is a finding. If the "space_left_action" is set to "exec", the system executes a designated script. If this script does not inform the SA of the event, this is a finding. If the "space_left_action" is set to "email" check the value of the "action_mail_acct" parameter with the following command: $ sudo grep action_mail_acct /etc/audit/auditd.conf action_mail_acct root@localhost The "action_mail_acct" parameter, if missing, defaults to "root". If the "action_mail_acct" parameter is not set to the email address of the SA and/or ISSO, this is a finding. Note: If the email address of the SA is on a remote system, a mail package must be available.