Adding a secondary router (ap + wired) depending from the main one: how?

Hi,
I'm trying to config, with a fresh install, a secondary router (the first one has already with openWRT), sharing both wired lan (so, it should work more or less as a switch) that the wifi network (so I should behave as an access point). I tried to rappresent everything with the figure. Hosts may be connectcted to the routers wired or wireless: all should be in the same private network.
immagine
I refer to second one as r2.
Now, if I install openWRT on this r2 and when it restart I connect it via lan port, it seems that r2 remains configured as a switch and everything goes when I connect a pc to it, but I have two problem: I can't access to the router (or I dont know how: whis is the ip? It operates just like a dumb switch right?) and I cannot config the wifi.
So, I tried to connect r1 to r2 through the wan port of this last. In this case r2 acts as a router and I can reach it on the ip that r1 gives r2, but of course if now I connect my pc to r2 It belongs to a different network.
Now, the first question is: what is the right config to start with? I think the second one, or am I wrong? Second, I understood that I have to disable the dhcp on r2 (where? in the lan interfaces? in the dhcp & dns menu?), but I have not found where to tell r2 that It has to use r1 dhcp and dns too. I tried also to disable dhcp on r2 and to config lan on it as a dhcp client and not static, but something went wrong and luci did not finalize the tasks.
Some advices? :slight_smile:

note: my final goal is to have something little different, like this in figure... it is possible and good for reliable reason? I wuold try this config becauase my provider select me for 2.5Gbps line but I think I will just give me 1Gbps for each port of the actual modem/router :slight_smile:
immagine

The second diagram will be quite complicated for a beginner or average user.
You can stick to the first diagram which is easy to implement, just to extend your network.

4 Likes

Yes the first one is the straightforward dumb AP. Basically you're going to turn off routing features leaving only the desired central function of a wireless to wired converter.

In the second case it would be entirely different from the first case. There are different ways to approach it. If your LAN links are limited to 1 Gb you would need two separate routers, two separate networks, with some hosts on each one. The two networks can be routed to each other to share LAN resources like printers.

Otherwise it would involve buying 10Gbe LAN equipment which is still rather expensive in the context of home use.

1 Like

Ok, I'm going to apply all of this as I supposed too, I think i mixed or undid some steps.
A doubt (that caused me to not see the dumb AP wiki): the so called dumb AP refers only to the wireless network or I can also use router r2's ports to connect wired hosts? Better, of course I can but I have to config something more or the wiki description for the dumb AP includes wired ports?

Wired ports are included too.

The result is a bridged LAN (no internal subnets) that will work fine for home and small networks. People can connect to the Dumb AP over Ethernet or Wi-Fi (using the configured SSID/password) and use to the existing network.

What make & model is router 2?

In almost all cases where there are four "LAN" Ethernet ports and one "WAN" port, there is an internal hardware switch between the ports, so you can plug the cable to the main network into one of the LAN ports and three additional LAN hosts into the other ports.

Changing the "WAN" port over to the LAN network will require reconfiguration that varies depending on the specific hardware.

Both routers are netgear r7800.

This step of the wiki is not clear (am I able to edit it, in case?)
'
Enter an IP address “next to” your main router on the field “IPv4 address”. (If your main router has IP 192.168.1.1, enter 192.168.1.2). Set DNS and gateway to point into your main router to enable internet access for the dumb AP itself
"
Tomorrow I try more and better, I looked for doing something like this but I have not found the fields to fill.
I think the wiki also miss or is very short about how config the wifi AP, I think one of the first steps is to extend the radio network joining the main one... Doesn't it?

What is not clear? You cannot find the IPv4 address field?
image

1 Like

thanks Trendy for the patience, I found almost everything, maybe yesterday I slept a few!
This description was not right for me
Then scroll down and select the checkbox “Ignore interface: Disable DHCP for this interface.”
is in another tab in my web interface (openwrt2020), nothing to scroll down :slight_smile:
Maybe last question: I also set

  • the dns server under Network => DHCP and DNS => General Settings=>DNS forwardings, putting there the ip of the main router, even if it was specified into the wiki. Is it an unnecessary step router r2 automatically forward dns request to r1? How does r2 knows it?
  • under Network => DHCP and DNS => General Settings, I unchecked "authoritative dhcp server". Is this step too unnecessary?

Maybe I can put WAN in the same VLAN of the other ports, just setting it here (pic is the standard untouched config), for r2:

Yes that is how to do it. Make all the external ports the same: Untagged in 1 and off in 2.

True, that has changed recently, I've fixed it.

It is mentioned to add the DNS under LAN interface in the wiki, not in the DHCP sector.

Very, since the dhcp server is disabled in step 7.

2 Likes

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.