Syslog messages appears on the wrong device after change of IP-address

Hi.

I recently changed a firewall and the syslog messages stopped working in LibreNMS when I changed IP-adress on the devices.

During the installation of the new firewall (FW-NEW) I had a temporary IP (192.168.80.3). The old firewall (FW-OLD) had 192.168.80.1. Both devices was registered in LibreNMS and syslog messages where shown under each device.

When i changed the firewalls FW-OLD got 192.168.80.4 and FW-NEW got 192.168.80.1. I updated the DNS-records and all the data seemed ok. But when i look under FW-NEW > Log > Syslog i only see messages before the migration. If I look under FW-OLD > Log > Syslog, then I see the syslog messages from FW-OLD.

Why is that? Is the IP-address for the devices registered somewhere for syslog? How can I correct this?

Per

For syslog processing, it is matched by hostname, then primary ip, then any ip.

Did you happen to change the hostname?

Ok.

No the hostname and fqdn are the same as before. Resolved IP under Device > Overview is also correct.

I mean on the device. Also, you can uncomment the logfile() line in syslog.php and check the output in logs/librenms.log

The hostnames of the devices (firewalls) are the same as before.

I rebooted the LibreNMS server and now it seems to work again. The logs appear on the correct device.

Odd, must have been cache reverse DNS.