Systemd by Zabbix agent 2 not working properly

[Backstage24]

Zabbix Server & Proxies: v 7.4.5
Zabbix Agent2; v7.4.4
Template Systemd by Zabbix agent 2: v 7.4-2

We have an issue because the LLDs of Systemd by Zabbix agent2.
There are a lot of the same machines (RHEL). On some of it, the LLD for Systemd is running properly, but some of it is not running. No warnings or errors are visible on the machine, on the proxy server etc.
The out of the box Template "Systemd by Zabbix agent 2" is linked via a Master Template on the machine.
A little bit fancy are the fact: on some machine it works on another one it not works. All machines are deployed with OSTree via Red Hat Ansible Automation. The configuration on all Machines are not different.
Do you have any hint for me?

[Viktors Fomics]

Hello

Systemd by Zabbix agent 2 relies on the systemd module in Agent2, first thing to check on the non-working machines would be if it is loaded. On the agent's start, all modules are listed in logs, so running sudo grep -oP "(?<=using plugin ')[^']+" /var/log/zabbix/zabbix_agent2.log after the agent's restart should list all modules.

Second thing would be to check the permissions: it could be that those are set differently on the seemingly identical machines. Assuming that the user running the agent is 'zabbix', the following command would help to check if that is the case: sudo -u zabbix -s systemctl list-units --all --type=service --no-pager --no-legend

[Backstage24]

Hello and thanks for your reply.

We has compaired the loaded modules. There are loaded the same modules on both hosts (bad and good host).
Also the systemd plugin was loaded on both hosts.

Jan 08 08:06:45 bad.host zabbix_agent2[1692049]: using plugin 'Systemd' (built-in) providing following interfaces: exporter, maximum capacity: 1000, active checks on start enabled: false

The units are readable by zabbix user, on both host the same list.

Do you have any further ideas?