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I'm trying to configure multiple static IP addresses on my new Asus RT-N66U router, I had fiber installed yesterday so my old Thomson router won't work any more unfortunately.

Previously I ran a number of telnet commands that meant if I had a machine on with a certain local IP address, it would then be given an external WAN address as appropriate -

However, I've been trawling through the Asus menus and cannot see a way to configure this, nor can I find a way of telneting into the router.

Any suggestions on what to try next please? I'm tempted by dd-wrt or asuswrt-merlin but very worried about possibly bricking my new £100 router... that being said, the router isn't much use to me right now anyway.


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IP addresses are assigned not to physical ports(where you plug in the Ethernet cable), but to computers' network interfaces (think of them as network cards).

Looking at your router's spec it is clear that there is one physical WAN port RJ45 and 4 LAN ports RJ45 and of course WiFi. So the router itself has 1 WAN interface - the IP address on that will depend on your ISP - usually automatically assigned by ISP servers. This will be the one "outside" address of your network that can be seen from internet, which you will check say by The router also has 2 LAN interfaces - a WiFi interface and a LAN interface, bridged. This will be the one "internal" address of your router - usually set to some private IP such as Although there are 4 RJ45 ports, you can think of them as a simple switch between your router and the rest of your LAN; there is one LAN address for your router, not 4.

What your commands seem to do is to set up some sort of quality of service setting so that certain traffic from some computers can be prioritised, but not assigning different external addresses to your computers. The "external" world will still see one address - that of your router's VAN interface and the router itself will translate addresses internally so that correct traffic ends up on the correct local computers. Unless you want to restrict/shape traffic for your LAN there should be no need for you to set anything via telnet. If you do - then go to Traffic Manager (page 28 in manual) and set up things as needed.

If for administrative purposes, includiong QoS you want to have static addresses on local network - you set them up on each local computer. You only need to see that the addresses fall in the same subnet as your router's internal interface IP. For example - if your router's internal address is with netmask (sometimes expressed as /24) then any address different for each LAN computer ranging from to with the same netmask should be fine. You of course would need to supply default route address ( and usually the same will serve as your DNS server. With DNS however you can use google's or

So to me, unless I have totally misunderstood, it seems there has been a little confusion in concepts and I hope this helps to clarify it. DD-wrt has a really nice interface and setting it up also helps with networking concepts. The danger of bricking always exists, but it is small and precautions are explained on their site.

1:1 mapping

Interesting, I looked this up. It apparently is called 1:1 address mapping. The idea is that you have a block of real/public IP addresses that your ISP knows to forward to your router, which then does the trick - also called 1 to 1 NAT or address mapping. Essentially it is about setting up firewall rules (which is likely what your commands in pastebin did). However you have to own those addresses - so that your ISP can forward those to your network. You can read interesting info here: and also here:

And this is likely exactly what you need from DD-WRT:

I have used their firmware and have been very happy with the results. I did buy cheaply on e-bay a linksys router which was known to be compatible with it.

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Thank you very much for the reply, however on the previous setup I did have static WAN IPs also, from just the one router... ie if I went to whatsmyip from a local machine with an IP of, it will allocate external IP1 to that accordingly. It does sound like DD-wrt is my best option in getting this setup though, thank you :) – Nick Feb 6 '14 at 14:52
Thanks for clarification. If you do not mind, could you give example of say 2 ip's that you used (that appeared on whatismyip? Who allocated them. The thing with real IP addresses is that they are assigned explicitly by the entity that owns the subnet those addresses are part of. – r0berts Feb 6 '14 at 18:54

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