I believe this will work. Replace <wan> <ns#.ip> with your setup where appropriate. Rest is about converting these lines to /etc/config/network and /etc/config/firewall or uci.
ip add add 56.52.53.2/29 dev <wan>
ip add add 56.52.53.3/29 dev <wan>
ip add add 56.52.53.4/29 dev <wan>
ip add add 56.52.53.5/29 dev <wan>
ip add add 56.52.53.6/29 dev <wan>
iptables -t nat -A zone_wan_prerouting -i <wan> -d 56.52.53.3 -p udp -m udp --dport 53 -j DNAT --to-destination <ns1.ip>:53
iptables -t nat -A zone_wan_prerouting -i <wan> -d 56.52.53.4 -p udp -m udp --dport 53 -j DNAT --to-destination <ns2.ip>:53
Since you insist on using non-OpenWrt commands, methods and syntax with OpenWrt, I won't be able to assist you.
This is not how the Wiki, manuals, etc. setup an OpenWrt device.
Also, user created rules are not recommended to be added to OpenWrt-created firewall chains.
This rule can be added using OpenWrt syntax (or just simply using the GUI)...so that it's added correctly
Why are you still improperly assigning all IPs to the router...I thought I also read you're assigning IPs to the devices...this is incorrect as I already noted
Why don't you use the web GUI as noted in the "step-by-step" instructions you requested yourself?
I'm confused why you asked for steps, then persist on undertaking other steps not suggested by anyone in the thread.
EDIT: I realize the post wasn't the OP. @ppmm your config (i.e. addining IPs to the router) is what caused the OP's issue.
I do think your example will open services for the OP on the desired IPs, though.
Yes, it would be a step-by-step if I know how to make a VLAN bridge!!! but I don't!
So what are the steps to make a VLAN bridge?
Since you insist on using non-OpenWrt commands, methods and syntax with OpenWrt,
I'm not insisting any anything, these are just suggestions from forum users.
Besides, I wouldn't know a non-OpenWrt command, method and syntax from an official one.
If you take just my Web server as an example, it must be assigned a static IP, then a rout to the internet via one of my LAN ports need to be established.
I am doing incorrectly because I don't know what I'm doing, and trying to get information that will help me understand so I can do it correctly.
I am using the GUI!!!!
I'm confused why you asked for steps, then persist on undertaking other steps not suggested by anyone in the thread.
You're confused... Persist? I have taken all information from this thread and implemented them. However, if you would read the thread from the perspective of someone who doesn't have your knowledge you would see how confusing this is.
Can you please be a little more choice-full in your language, you are coming over as angry and impatient?
I really appreciate your input and its frustrating enough without having to explain my misunderstandings.
The problem is that you have assumed that the NS is sitting behind a NAT and unfortunately my Domain provider states the address has to be public... Or have I got that bit wrong?