Create graph juniper class of service

Please help, i am newbe using librrnms, i need to monitor class of service (cos) traffic frim router juniper m10i. Is there any manual how to create cos graph ? Thanks.

[root@LibreNMS librenms]# ./validate.php

Component Version
LibreNMS 1.44-30-gf8ec6c5
DB Schema 269
PHP 5.6.38
MySQL 5.5.60-MariaDB
RRDTool 1.6.0
SNMP NET-SNMP 5.7.2

====================================

[OK] Composer Version: 1.7.2
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct