TL-ER6020 - custom DNS server not working
I have migrated from a Fritzbox to the TL-ER6020, mostly because of WAN-loadbalancing and failover. So far the setup of the router has been pretty smooth, I've just got one problem that's really bugging me:
Setting up custom DNS servers doesn't seem to be working.
I'm using a Raspberry Pi with Pi-hole installed to filter ads, insecure domains, family-unfriendly-content, and so on.
Using the Fritzbox it was pretty easy: the pi-hole (192.168.2.30 in my case) was set up as its primary DNS server and successfully resolved DNS-queries, filtering all the stuff I don't want to see.
Setting up the pi-hole as the primary DNS on each WAN-port (currently only one is active) on the TL-ER6020 seems to be getting ignored by the router. The pi-hole doesn't get any DNS-request from it, and no content is filtered or blocked.
I hope someone can help me resolve this issue, thanks in advance! :-)