Use pi-hole lxc with a genexis router without admin rights

genexis PURE-F500-OPT-4.3.6.150-R
pi-hole 6.4.2
proxmox VE 9.1.9

I did this with a raspberry years ago and shut it down at some point. Now I wanted to do it again with a lxc on proxmox and found that I am not able to change the DNS server in the genexis router anymore, because the standard admin user did not work.

In the end it was not that hard to get it running, you just have to inactivate the DHCP server on the router and use the pi-hole for this.
You can do this here:

My first attempt was to add a DNS server to the DHCP server on the router, but somehow this did nothing, still the DNS from the WAN settings took over. And I did not find a way to change these.

When the DHCP from the router was gone and the pi-hole DHCP was active, all the non static clients used it. 

 PURE-F500-OPT-4.3.6.150-RPURE-F500-OPT-4.3.6.150-RPURE-F500-OPT-4.3.6.150-R PURE-F500-OPT-4.3.6.150-RPURE-F500-OPT-4.3.6.150-R