Update to redis 5 - Service stops working

Hello and good day,

today I upgraded the redis database, and shortly after one of my servers stopped polling the devices in it’s group. After checking the logs this seemed to be the main issue:

redis.exceptions.ResponseError: WRONGTYPE Operation against a key holding the wrong kind of value

I can provide more logging on request.

This happens when the database is redis 5.x. I tried to roll back the database version to see if i would get my devices to get polled by the service again. On redis 3.2.x the server where the redis database is not hosted starts working, but the one who is connecting to localhost stops working. I don’t have the logs for this on hand but it would not be too hard to reproduce .

I have the following setup:


Server 1:
Master.nms.server

  • rrdcached
  • memcached
  • web server
  • Mysql instance

Here is the output of validate.php

Component Version
LibreNMS 1.51
DB Schema 2019_02_10_220000_add_dates_to_fdb (132)
PHP 7.2.13
MySQL 5.5.60-MariaDB
RRDTool 1.6.0
SNMP NET-SNMP 5.7.2

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

[OK] Composer Version: 1.8.5
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct



Server 2:
Poller.nms.server
This is just a poller. It acts as a load blaancer for the location with the most polled devices.
Hosted here:

  • Redis database

Output of validate.php

Component Version
LibreNMS 1.51-68-g2dc05ee
DB Schema 2019_02_10_220000_add_dates_to_fdb (132)
PHP 7.2.17
MySQL 5.5.60-MariaDB
RRDTool 1.6.0
SNMP NET-SNMP 5.7.2

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

[OK] Composer Version: 1.8.5
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct


Everything is set up according to the new documnetation and is currently working “fine”.

My current workaround is to use cron jobs on master.nms.server, but i would really like to use the service as it is much better, both in performance and administration.

Any help is greatly appreciated!