How to configure the router when the gateway is in bridge mode?

Question

I was given a VDSL gateway (ZyXel) by my ISP (online.nl) whose performance is low, and therefore I bought a router (ASUS RT-AC66U) to improve the LAN/WLAN/home networking performance.

Therefore I want to have something similar to this:

I want my NAS to be connected to the Internet and therefore only one routing with NAT is enough and thus I bridged mode the gateway. I know how to bridge mode the gateway, but every time I do it, I lose internet connection.

• Do I need to do something special in the router when I setup the gateway to bridge mode? Which exact WAN configurations?

• Can the router work directly as a VDSL gateway, removing then the gateway provided by the ISP?

Solution 1

Just to let the readers know the solution I found for my issue (now, it's working like a charm):

Cabling

Connect the LAN port (LAN1 to be sure) of the gateway (gateway=modem+router, in my case a ZyXel) to the WAN port of the router (in my case ASUS RT-AC66U)

Something similar to this (hardware brands are just exemplary):

Gateway

On the gateway GUI/portal:

1. go to "broadband" section or similar, set it to bridge mode
2. go to "home networking" section or similar, disable DHCP
3. go to "security" section or similar, disable firewall

Router

On the router GUI or portal, got to WAN section:

1. clone MAC address (your ISP may block any device except the one with the MAC address of the known gateway). My router has that option:

2. set to automatic IP or DHCP (if your ISP does not give you a static IP, like it is normal)

3. in my ASUS I still set DHCP query frequency to "normal" instead of "agressive"

Conclusion

Now I really have a nice bridged network between both routers, that is the 1st router (embedded in the gateway) and the 2nd router, being my 2nd router the main only true router (routing data with firewall, NAT, etc.) and not being merely a repeater or an access point.

I did this because the 1st router provided by my ISP has much poorer performance than the 2nd router which I bought separately.

Solution 2

I would just like you to note that exposing a NAS to the Internet may be a big security hole. NAS devices are not well protected, and when infected can easily infect every other device on the local network.

Thus warned, here are some answers.

Do I need to do something special in the router when I setup the gateway to bridge mode? Which exact WAN configurations?

You have set up a double-NAT situation by connecting the ZyXel to the WAN port of the ASUS router. Connecting the ZyXel LANx to an Asus LANx port will make the network into single-NAT.

For more information see :

• this answer of mine.
• Port Forwarding Guides for ZyXEL routers

Can the router work directly as a VDSL gateway, removing then the gateway provided by the ISP?

The AC66U does not support VDSL, so you can't get rid of the modem.

Comments

[harrymc]

The text-labels in the image do not match the question text. What is the P-2601HN-F1? RT-AC66U or N66U? If N66U, why do you need the other modem?

[João Pimentel Ferreira]

@harrymc yes, the image is merely an example. Do you mean why do I need the router? To improve Wi-fi and CPU performance. The gateway given by the ISP is really poor.

[harrymc]

The AC66U does not support VDSL, so you can't get rid of the modem. Where here is the DHCP master? I also don't understand your first question.

[João Pimentel Ferreira]

@harrymc what do you mean by DHCP master? The question is: if the gateway is in bridge mode, what WAN settings shall I put in the router?

[harrymc]

I mean which box is master and which only a repeater.

[João Pimentel Ferreira]

@harrymc I have no repeaters. I have a ZyXel VDSL gateway that connects to the Internet, and whose port LAN1 then connects to the WAN port of the ASUS router.

[João Pimentel Ferreira]

Thanks, I read your great answer. But I have a gateway not a modem. May I assume that my gateway is equivalent as a modem+1st router?

[harrymc]

Yes, that's the way things work for just about all devices.

[João Pimentel Ferreira]

If I configure the ZyXel as bridge mode, may my asus work as primary router (zyxel LAN -> asus WAN)?

[João Pimentel Ferreira]

Regarding your answer on the second configuration (LAN to WAN) what happens if I configure the first router to bridge mode? Will it be similar to the first configuration? I want my asus to be the main router and not merely a repeater.

[harrymc]

The answer is positive, if bridge mode turns off the ZyXel DHCP-master function, requiring perhaps giving it a static IP that is excluded from the Asus DHCP IP address-range (as well as other adjustments as required). As the Asus is a better device, that may give more control of the network.

[João Pimentel Ferreira]

Thanks again for the answer; btw, can you also check my answer just to be sure that I wrote everything correctly? In any case your answer is the accepted one.

[harrymc]

Nicely written, no problem that I can see. Enjoy.

[João Pimentel Ferreira]

@harrymc thank you

[m1nkeh]

hey, i know this thread is mega old... but what did you do about WiFi on the Zyxel? Ty!

[João Pimentel Ferreira]

@m1nkeh I switched it off to avoid duplication of networks. But pay attention that if you switch it off you can no longer configure the Zyxel via wifi. Thus just switch it off after every setting is complete and running smoothly