Flint (GL-AX1800) DNSMasq (DHCP) issue

Technical Support for Routers
1

I would like to share a problem with a Flint (GL-AX1800) router configured as in router mode, in a small business (3 devices connected to it)
OpenVPN and Wireguard are set up and working since 2 years.
The problem: without any reasons the 3 devices connected to the router (a Synology, a Windows 2022 server, and a TPLink CPL device) were not able to connect anymore. Nothing changed during the past 2 years on the network!

The server IP address is 192.168.8.1 and the DHCP range is 192.168.8.10-150
In the network client page of the router, I saw that the 3 devices had unconsistant IP address, not corresponding to the IP range of the DHCP server. (like 192.168.0.xxx)
In the logs, I noticed that dnsmasq was complaining that there were no IP available in range for br-lan (!!!) Yes, there are 3 devices on the network...

daemon.warn dnsmasq-dhcp[XXXX]: no address range available for DHCP request via br-lan

I upgraded the firmware from 4.1.0 (2022-11-14) to the latest available: 4.6.6 (2024-09-26)
Then everything is back to normal and the 3 servers are online with a correct IP address in the range of 192.168.8.x
Home it can helps though I still don't know what was this weird bug.
Any idea?

2

Seems that the DHCP pool wasn't in range of the DHCP leases. I don't know how this could happen but since it disappears and you were using a really old firmware I would simply accept it. :slight_smile:

3

The DHCP range was well defined and on the same network range as the IP address of the router. Anyway, updating the firmware solved the issue but it's kinda of frustrating not to know what was wrong :slight_smile: