Non-Standard netmasks does not work on Cudy WR3000 with openWRT 25.12.3

Installing and Using OpenWrt Network and Wireless Configuration
1

Hi,

I am using openWRT to route in between subnets of the ampr.org (44.0.0.0/8) network. Therfore I have to define interfaces with subnets with non standard netmasks like 255.255.255.224. Currently I am using a TP-Link Archer C6 with openWRT 24.10.4 which works fine.

Now I want to replace the hardware with a cudy WR3000S. The cudy is flashed with an openWRT 25.12.3. As long as I use a standard subnet like /24 everthing works fine as expected. A /26 subnet worked fine as well, but it seems to be unstable (meaning sometimes it works, sometime not) when I try to define a /27 subnet it does not work at all.

"does not work" means that a connected device does not get any information from DHCP and it is not possible to send and receive any frames. When I change the configuration to a /24 subnet again it works fine again.

Is there any known issue either with the cudy device or with openWRT 25.12?

best regards,

Holger

2

Are you using Wireguard (AMPR Connect) or legacy IPENCAP?

Otherwise, where are you routing the submets (from where to where)?

(I'm an IPENCAP user if you ever need to test.)

Let's see the /etc/config/dhcp file.