VMG Zyxel gateway

pether

I have got the following VMG router (what Zyxel calls) from my ISP operator in the Czech Republic (see an example here - it is very hard to identify):

https://pc.bazos.cz/inzerat/196594180/modem-gateway-od-o2.php)

I am trying to set my custom DHCP server (that's a device on a wifi network) but as soon as I do it - the outgoing connectivity stops working. I have been trying to sshing into the box and got to ZySH, however that's a very simple interface that does not really allow to see VLAN tagging and other stuff….

Why does setting "DHCP relay" screw up the entire network? Is it because the DHCP box is on the wifi network? 10.0.0.220 is a pihole box with dhcp server turned on that points to a privacy DNS servers (and also is connected to the default wifi network over wifi)

After setting this and re-authenticating to wifi I lose ping outside, connectivity outside, but the local wifi stays OK.

cheers,

pehter