Logrotate cron task in Plesk fails: skipping because parent directory has insecure permissions

Symptoms

The Plesk administrator receives alerts with the following content indicating the task /etc/cron.daily/logrotate failed:

CONFIG_TEXT: /etc/cron.daily/logrotate
error: skipping "/var/log/newrelic/php_agent.log" because parent directory has insecure permissions (It's world writable or writable by group which is not "root") Set "su" directive in config file to tell logrotate which user/group should be used for rotation.
error: skipping "/var/log/newrelic/nrsysmond.log" because parent directory has insecure permissions (It's world writable or writable by group which is not "root") Set "su" directive in config file to tell logrotate which user/group should be used for rotation.
run-parts: /etc/cron.daily/logrotate exited with return code 1

Cause

Incorrect permissions and/or ownership on parent directory/directories.

Resolution

1. Connect to the server via SSH.

2. Set the correct permissions and ownerships on the parent directories:

   # chmod 755 /var/log/ && chown root:root /var/log/
   # chmod 755 /var/log/newrelic && chown root:root /var/log/newrelic
   # chmod 755 /var && chown root:root /var

Note: if Ubuntu is used, make sure that su root syslog is included into /etc/logrotate.conf file:

# head /etc/logrotate.conf
# see "man logrotate" for details
# rotate log files weekly
weekly

# use the syslog group by default, since this is the owning group
# of /var/log/syslog.
su root syslog

# keep 4 weeks worth of backlogs
rotate 4