Graphs Not Drawing in LibreNMS

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1

Hello

im facing an issue with LibreNMS where the graphs are either completely empty or have stopped updating recently. The polling seems to be working based on the logs, and services are running fine

librenms@librenms:~$ ./validate.php 
===========================================
Component | Version
--------- | -------
LibreNMS  | 25.6.0 (2025-06-16T13:55:12+02:00)
DB Schema | 2025_06_11_025425_hr_device_table_add_status_default (343)
PHP       | 8.3.14
Python    | 3.8.10
Database  | MariaDB 10.3.39-MariaDB-0ubuntu0.20.04.2
RRDTool   | 1.7.2
SNMP      | 5.8
===========================================

[OK]    Composer Version: 2.8.9
[OK]    Dependencies up-to-date.
[OK]    Database Connected
[OK]    Database Schema is current
[OK]    SQL Server meets minimum requirements
[OK]    lower_case_table_names is enabled
[OK]    MySQL engine is optimal
[OK]    Database and column collations are correct
[OK]    Database schema correct
[OK]    MySQL and PHP time match
[OK]    Active pollers found
[OK]    Dispatcher Service is enabled
[OK]    Locks are functional
[OK]    Python wrapper cron entry is not present
[OK]    Redis is unavailable
[OK]    rrdtool version ok
[OK]    Connected to rrdcached

Screenshot 2025-06-29 at 10.29.24 PM
Screenshot 2025-06-29 at 10.29.24 PM1920×556 93.2 KB

2

hmm, I wonder what graph or type of device this is…

3

Hello

This is traffic data for MikroTik devices. I have two LibreNMS instances: one where the graphs are working correctly, and the other where they are not displaying at all. Below is some information from both systems:

Working instance:
librenms@librenms:~/rrd/172.16.150.1$ rrdtool fetch sensor-voltage-routeros-0.rrd AVERAGE --start -1h --end now

sensor

1751299200: 24.0000000000

1751299500: 24.0000000000

1751299800: 24.0000000000

1751300100: 24.0000000000

1751300400: 24.0000000000

1751300700: 24.0000000000

1751301000: 24.0000000000

1751301300: 24.0000000000

1751301600: 24.0000000000

1751301900: 24.0000000000

1751302200: -nan

1751302500: -nan

1751302800: -nan

Instance with graphs not drawing:

librenms@librenms:~/rrd/172.16.150.1$ rrdtool fetch sensor-voltage-routeros-0.rrd AVERAGE --start -1h --end now

sensor

1751299200: -nan

1751299500: -nan

1751299800: -nan

1751300100: -nan

1751300400: -nan

1751300700: -nan

1751301000: -nan

1751301300: -nan

1751301600: -nan

1751301900: -nan

1751302200: -nan

1751302500: -nan

1751302800: -nan

4

How about the poller debug output?