GT-AX6000 AiMesh: clients getting knocked off

[DianaRea]

Hello,

This is my first post here.

I had a ASUS GT-AX6000 wifi router for a few years which worked excellent.
I recently moved to a new place in which the single access point cannot cover the premises.
So I figured that I needed one more ASUS GT-AX6000 to extend the wifi coverage and that AiMesh would probbly be ideal for that.


So now I have two ASUS GT-AX6000 wifi routers. I have CAT6a cable between them.
Both have the Asus Merlin firmware on them version 3004.388.4

I have set these up for AiMesh. The new one being the node, the old one being primary.

Ethernet cable is connected from mesh node's 2.5GbE LAN port to the primary's first 1GbE port.
I have enabled "Ethernet Backhaul Mode".
On the mesh node, I have set it to prefer 2.5GbE LAN for backhaul.

According to the GUI, all seems OK.

However, when I power on the mesh node, the devices using wifi keeps getting disconnected.
At first I thought I had accidentially made a switch loop and that this was what killed the network, but this appears not to be the case because all the ethernet connected devices work just fine.

What seems to happen on the wifi clients is that they are able to connect to the wifi but the OS reports "no internet connectivity".
The clients are a mix of MacOS and Windows.

My network topology is like this:

Internet is provided via fiber modem in "bridge mode".
Fiber modem is connected to WAN port on the primary RT-AX6000.
Primary RT-AX6000 is the default gateway for all the network nodes.

Network configuration is provided via DHCP on a Linux server.
(DHCP is disabled on the primary RT-AX6000)

DNS is provided by two Linux servers. (primary and secondary DNS)
The primary is doing DNS based adfiltering via pihole.


The Primary RT-AX6000 has 4 1GbE LAN ports + 1 2.5GbE LAN port.
The 2.5GbE port is unused.
First 1GbE port is connected to the mesh node RT-AX6000.
Second 1GbE port is connected to an HP 1GbE switch to which all the remaining ethernet devices are connected.


My questions to you are:


1: What may be wrong with my setup causing the wifi to not work when the mesh node is connected? Is this a known problem?

2: Is it a problem that I have the ASUS Merlin firmware on the mesh node? Should I rather have kept it to the vanilla firmware?

3: Any idea how to fix this?

4: Am I approaching this the wrong way? I mean, poor wifi coverage was the reason I even started going down the AiMesh path. But now I start doubting that mesh is even the right approach. Are there better alternatives? I think there are also products like wifi repeaters/wifi extenders. Would they be better suitable here?

 

[DianaRea]

I was thinking that perhaps I should have kept the mesh node on the stock Asus firmware. However, according to the Merlin documentation (https://github.com/RMerl/asuswrt-merlin.ng/wiki/AiMesh), this does not seem to be required.

Asuswrt-Merlin 384.13 adds full support for AiMesh (both as a primary router and as a node). Nodes can run either stock Asus or Asuswrt-Merlin

The docs mention one limitation when using Merlin firmware on node, but this does not seem relevant here:

Nodes running this firmware will have one limitation over running on the stock firmware, which is they will lack the ability to automatically download and install new firmware versions. New firmware availability notification will still work, and the changelog will also be visible through the webui, but you will have to use the node's Upload hyperlink to manually upload any new firmware. Nodes running on the stock firmware will retain their ability to do live updates by using the global Firmware Upgrade button.

So I guess I can ignore that part?



Another thing I found in the documentation:

Note that AiMesh can sometimes be less stable than using a plain router + access point or repeater configuration due to the increased complexity of sharing configuration between the main router and its node(s).

This seems to hint that there might be a better approach than AiMesh.
What is meant by plain router + access point or repeater config?
Does this mean that I just set up two identical wifi configurations?

 

[Tech9]

AiMesh Wiki page was last edited in 2019. Stock firmware for your routers is 3006 base, Asuswrt-Merlin is 3004 base. If you don’t use any of the advanced Asuswrt-Merlin features like VPN Director or Custom Scripts - try stock 3006 on both. It adds SD WAN, user configurable VLAN support, Guest Network Pro, Captive Portal.

 

[DianaRea]

Added screenshot of mesh node config

aimesh config

primary config:

 

[DianaRea]

AiMesh Wiki page was last edited in 2019. Stock firmware for your routers is 3006 base, Asuswrt-Merlin is 3004 base. If you don’t use any of the advanced Asuswrt-Merlin features like VPN Director or Custom Scripts - try stock 3006 on both. It adds SD WAN, user configurable VLAN support, Guest Network Pro, Captive Portal.

I see.
So, I could try loading stock firmware on the mesh node. But I would really hope I could avoid using the stock firmware on the primary... I mean, if I have to, I have to, I guess. But I would really like to avoid.

Am I right that just flashing the mesh node with Asus stock firmware 3006 would not work as primary and node would have to be identical versions?

Could I flash node to stock 3004 firmware? Would this likely fix anything?


I see there is a 3006 version of merlin firmware. Is this not compatible with the GT-AX6000?

 

[Tech9]

Try stock firmware on the node first. There is no 3006 Asuswrt-Merlin for this model at the moment. Don’t flash older firmware versions, the last firmware fixes security issue.

 

[DianaRea]

Try stock firmware on the node first. There is no 3006 Asuswrt-Merlin for this model at the moment. Don’t flash older firmware versions, the last firmware fixes security issue.

Got it. Flashing mesh node with stock 3006 now.

Will report back how it goes...

Waiting a bit with the primary...

 

[DianaRea]

Mesh node is flashed with stock 3006 now. Waiting to see if I get any complaints about this not working

 

[bbunge]

With Ethernet Backhaul mode enabled you do not have to set the other connection priorities.
I have found that leaving the AiMesh settings to their default (Auto) works best for most folks. I have Ethernet Backhaul mode enabled and have turned off WPS in the Wireless settings. I use the 2.5 GB ports to connect the router to node with CAT 5e cable. I do not do this for the bandwidth but just because it is an extra port on the router.
Does not seem to matter which firmware you use on the router or nodes. Many do recommend Asus firmware on the nodes but my testing does not show that is right.

 

[Tech9]

Mesh node is flashed with stock 3006 now.

Many folks around are using Asuswrt-Merlin on main and stock Asuswrt on node(s). There is no real benefit of Asuswrt-Merlin on nodes, there is no routing there, they are Repeater (wireless) or Access Point (wired). If the main goal is AiMesh I would run the same 3006 stock firmware on both. For this router it's newer Asuswrt 5.0 firmware with features not present in Asuswrt-Merlin at the moment. The real benefit of Asuswrt-Merlin is in advanced VPN configurations and Custom Scripts ecosystem. Everything else is available now in stock Asuswrt one way or another. Both firmware versions are stable and secure enough. Keep in mind Asus removed all old firmware versions for your router including 3004 and you may not be able to flash back to Asuswrt-Merlin in GUI. One of the last Asuswrt versions is now minimum required for this model.