Need to change ownership to zextras user on /etc/carbonio/carbonio-prometheus-mysqld-exporter directory and run set-carbonio-prometheus-mysqld-exporter.sh from zextras usrer.

Anybody, give me, pleace, sample of /etc/carbonio/carbonio-prometheus-mysqld-exporter/carbonio-prometheus-mysqld-exporter.cnf

Because:

# journalctl -u carbonio-prometheus-mysqld-exporter.service
Feb 13 15:56:26 mail-store.neolabs.net carbonio-prometheus-mysqld-exporter: ts=2024-02-13T09:56:26.477Z caller=config.go:150 level=error msg="failed to validate config" section=client err="no user specified in section or parent"
Feb 13 15:56:26 mail-store.neolabs.net carbonio-prometheus-mysqld-exporter: ts=2024-02-13T09:56:26.477Z caller=mysqld_exporter.go:225 level=info msg="Error parsing host config" file=/etc/carbonio/carbonio-prometheus-mysqld-exporter/carbonio-prometheus-mysqld-exporter.cnf err="no configuration found"
# ls -la /etc/carbonio/carbonio-prometheus-mysqld-exporter/
total 0
drwxr-xr-x 2 root root  6 Feb 13 14:23 .
drwxr-xr-x 6 root root 93 Feb 13 14:29 ..
# 

Apparently they forgot to put it in the package again. :)