Currently, LibreNMS does not associate shortnames from Graylog with full FQDNS. If you have your devices in LibreNMS using full FQDNs, such as hostname.example.com, be aware that rsyslogd, by default, sends the shortname only. To fix this, add
`$PreserveFQDN on`
to your rsyslog config to send the full FQDN so device logs will be associated correctly in LibreNMS
If you choose to use another user besides the admin user, please note that currently you must give the user "admin" permissions from within Graylog, "read" permissions alone are not sufficient.