How to properly set-up two routers and one modem?

[NeoXx]

I ordered two ASUS RT-AC88U routers and I will be connecting both of them to my modem via Ethernet cables.
The routers will be on separate floors.
I couldn't find complete information how to properly set them up. From my understanding I should
do the following:

Modem:
-Set IP for example 192.168.1.1 and turn on DHCP with a range 192.168.1.4-192.168.1.xxx

Router One:
-Set IP 192.168.1.2 and turn off DHCP

Router Two:
-Set IP 192.168.1.3 and turn off DHCP

In other words, let the modem assign IP's (by having DHCP on), and set IP addresses of both routers
to be outside the DHCP range.

Now what about NAT?
Also I never owned such advanced routers before, should I set them up in some specific mode (bridge mode?).

P.S. I'll be installing Merlin firmware.

Thank you

 

[lighting]

I ordered two ASUS RT-AC88U routers and I will be connecting both of them to my modem via Ethernet cables.
The routers will be on separate floors.
I couldn't find complete information how to properly set them up. From my understanding I should
do the following:

Modem:
-Set IP for example 192.168.1.1 and turn on DHCP with a range 192.168.1.4-192.168.1.xxx

Router One:
-Set IP 192.168.1.2 and turn off DHCP

Router Two:
-Set IP 192.168.1.3 and turn off DHCP

In other words, let the modem assign IP's (by having DHCP on), and set IP addresses of both routers
to be outside the DHCP range.

Now what about NAT?
Also I never owned such advanced routers before, should I set them up in some specific mode (bridge mode?).

P.S. I'll be installing Merlin firmware.

Thank you

Lots of folks out there know more than I do, but... I'm guessing you want just one subnet so devices can communicate within your network, and the second router is to provide better wifi coverage? If so you want to set up one RT-AC88U to be the primary router, communicating with the modem as you suggest, and doing the DHCP and routing for all the devices in your network. And the second router should be in Access Point mode (for which an RT-AC88U is overkill but should work fine). The access point plugs into a LAN port on the primary router, not into the modem. I don't think you want the modem providing DHCP service for anything but the primary router's WAN side. Hope that's helpful.

 

[CaptainSTX]

The setup you are describing is using both of your AC88s as APs. The AC88s allow you to select a predefined AP mode which will turn off the DHCP server. Just be sure the cable coming from your modem connects to a LAN port on the AC88s. When the AC88s are in the AP mode you have the option to use the WAN port as a LAN port.

When you have set a router to operate as just an AP most of the features are unavailable/disabled/turned off. If you only want/need AC WiFi radios you might consider using less expensive hardware.

If you want to use the AC88s features you will need to double NAT them so they remain in the router mode. There are reasons to do this and it can work well if you want/need a strict segregation between subnets. I choose to run my network this way and it works fine.

 

[NeoXx]

Lots of folks out there know more than I do, but... I'm guessing you want just one subnet so devices can communicate within your network, and the second router is to provide better wifi coverage? If so you want to set up one RT-AC88U to be the primary router, communicating with the modem as you suggest, and doing the DHCP and routing for all the devices in your network. And the second router should be in Access Point mode (for which an RT-AC88U is overkill but should work fine). The access point plugs into a LAN port on the primary router, not into the modem. I don't think you want the modem providing DHCP service for anything but the primary router's WAN side. Hope that's helpful.

The setup you are describing is using both of your AC88s as APs. The AC88s allow you to select a predefined AP mode which will turn off the DHCP server. Just be sure the cable coming from your modem connects to a LAN port on the AC88s. When the AC88s are in the AP mode you have the option to use the WAN port as a LAN port.

When you have set a router to operate as just an AP most of the features are unavailable/disabled/turned off. If you only want/need AC WiFi radios you might consider using less expensive hardware.

If you want to use the AC88s features you will need to double NAT them so they remain in the router mode. There are reasons to do this and it can work well if you want/need a strict segregation between subnets. I choose to run my network this way and it works fine.

So getting a second RT-AC88U was probably a mistake, should have bought an AP instead.
Nevertheless CaptainSTX has mentioned double NAT, since obviously I would prefer to use both of the routers' features rather
than set one as an AP since it would be a waste of money.

If I double NAT, couldn't I just set different DHCP ranges on both routers in order to avoid IP conflict?
What are the disadvantages?

 

[CaptainSTX]

I use a double NAT currently to segregate my Iot devices from my more secure devices. I have used a double NATed setup on and off for the past seven years. Without going into the reasons you might want to do it here are some of the cons:
1. If you want or need to share devices between the multiple subnets it will be difficult and may require customized routing.
2. Port forwarding if required will be more complicated.
3. Administering both routers requires twice the effort and depending on how you set things up and which subnet the PC is connected to may require that you change your connection and connect to the network you wish to administer.
4. If you have troubles with your network lots of people, particularly those that don't use a double NATed setup, will almost automatically try to blame the problems on the double NAT setup and strongly recommend that you not do it.
5. Using a dynamic DNS may or may not be possible on the router double NATed behind the Internet facing router. I can make it work using Tomato, but not ASUS or Merlin firmware,
6. Adding any network device to your network, be it a double NATed router, AP or switch will add several ms to your latency.
7. In the spirit of KISS double NATing probably is not worth doing if you don't have a good reason. In your case taking advantage of the expensive routers you have might not be a good enough reason. Nothing to lose by trying if you can live with the cons mentioned above and I'm sure others on this forum can add to the list.

 

[NeoXx]

I use a double NAT currently to segregate my Iot devices from my more secure devices. I have used a double NATed setup on and off for the past seven years. Without going into the reasons you might want to do it here are some of the cons:
1. If you want or need to share devices between the multiple subnets it will be difficult and may require customized routing.
2. Port forwarding if required will be more complicated.
3. Administering both routers requires twice the effort and depending on how you set things up and which subnet the PC is connected to may require that you change your connection and connect to the network you wish to administer.
4. If you have troubles with your network lots of people, particularly those that don't use a double NATed setup, will almost automatically try to blame the problems on the double NAT setup and strongly recommend that you not do it.
5. Using a dynamic DNS may or may not be possible on the router double NATed behind the Internet facing router. I can make it work using Tomato, but not ASUS or Merlin firmware,
6. Adding any network device to your network, be it a double NATed router, AP or switch will add several ms to your latency.
7. In the spirit of KISS double NATing probably is not worth doing if you don't have a good reason. In your case taking advantage of the expensive routers you have might not be a good enough reason. Nothing to lose by trying if you can live with the cons mentioned above and I'm sure others on this forum can add to the list.

Thank you very much for the help.

A few quick questions:

1. I assume if I double NAT I will have two separate networks?
2. Is several extra ms in latency noticeably?
3. Will a client connected to an AP (where AP is connected to the main AC88U router) be able
to take advantage of the main routers' capabilities?

If I were to return one AC88U router I would get a high-end consumer AP which costs around 200 usd (a bit less than AC88U).
Would AC88U's wireless capabilities rival a high-end AP? If yes, there isn't much reason to swap the router for an AP due to small
price difference. If what we discussed above does not work, I will then set one AC88U as an AP.

 

[CaptainSTX]

Thank you very much for the help.

A few quick questions:

1. I assume if I double NAT I will have two separate networks?

Yes or if you keep your original routers plus the two 88s you could have three networks.

2. Is several extra ms in latency noticeably?

Basic physics the ms are quantifiable and measurable. Unless you are a quant or a professional gamer will sever ms make a difference probably not.

3. Will a client connected to an AP (where AP is connected to the main AC88U router) be able
to take advantage of the main routers' capabilities?

Any device connected to the AP will utilize all the features on the main AC88. While you can turn on the radios on the AP and set up guest networks they won't be isolated from your primary network. If you want isolated/segregated guest networks they need to be on your primary router.

If I were to return one AC88U router I would get a high-end consumer AP which costs around 200 usd (a bit less than AC88U).
Would AC88U's wireless capabilities rival a high-end AP? If yes, there isn't much reason to swap the router for an AP due to small
price difference. If what we discussed above does not work, I will then set one AC88U as an AP.

The AC58/ 1900 series ASUS routers make excellent APs and are probably over kill. The AC88 is over the top. Will probably work great, but it just isn't cost effective for most people..

 

[Mark88]

Modem:
-Set IP for example 192.168.1.1 and turn on DHCP with a range 192.168.1.4-192.168.1.xxx

Router One:
-Set IP 192.168.1.2 and turn off DHCP

Router Two:
-Set IP 192.168.1.3 and turn off DHCP

maybe this 192-168-1.1 instruction will help you. I've used it to set up my router and my friend's modem. Everything is working great)))

 

[CaptainSTX]

Modem:
-Set IP for example 192.168.1.1 and turn on DHCP with a range 192.168.1.4-192.168.1.xxx

Router One:
-Set IP 192.168.1.2 and turn off DHCP

Router Two:
-Set IP 192.168.1.3 and turn off DHCP

http://192-168-1-1.one/ - maybe this instruction will help you. I've used it to set up my router and my friend's modem. Everything is working great)))

He needs or wants to double NAT. Your instructions are to turn a router into an AP.