Adding an ASUS RT-AC66U B1 to an existing network as an AI-Mesh Node

I had some difficulty adding a brand new ASUS RT-AC66U B1 to my home network. My network consists of an ASUS GT-AC5300 and two TP-Link AC1200 Wi-Fi Range Extenders (RE355). These range extenders worked substantially better than the previous TP-Link N300 Wi-Fi Range Extenders (TL-WA860RE) in regards to signal, but the main problem I had with the RE55s was that any time the power went out or I had to reset my GT-5300, I would have to power cycle the Range Extenders to get them to come up again.

Note: For ease of typing/clarity, below I will refer to the RT-AC66U_B1 as the AC66U and the GT-AC5300 as the GT-5300.

Being the glutton for punishment I am, I took faith in that a mesh system that’s a year or so old should work out of the box.  Wrong!  So, I first tried to just turn on the brand new AC66U, connected to it via wireless, followed the wizard to set it up as a Mesh Node.  Once it rebooted, I then went into the AI-Mesh management feature on the GT-5300, and clicked the Search button on the “Find AiMesh Node” screen. It found the new router, but after around 40% complete, I got an error message that setup could not be completed and it listed several generic reasons.  (As an aside, I sent a very detailed message to ASUS tech support with most of what I tried below, including firmware versions, logs, etc.. and they sent me back the same generic reasons from the error message and to please try again!)

So, I figured that even though this was a new unit, the firmware on the AC66U may not be the latest and greatest (even though it said it supported AiMesh and manufacture date was March 2018), I downloaded the latest firmware to my iPad, then connected to the AC66U and ran through the setup wizard and told it to use the normal Router mode. I ignored an error that there was no network cable plugged in, and it went right on through. After the router rebooted, I connected to the new 5ghz network wirelessly and upgraded the firmware via upload from my iPad. It rebooted and I logged in again. I went into the AC66U Mode page and switched it from Router to AiMesh Node. Let it reboot and crossed my fingers. No dice.

I wasted a few hours of downgrading firmware versions on both the AC66U and the GT-5300. I didn’t have any success.  Literally the next morning, about 6 hours into it, I upgraded both routers back to the latest firmwares (Version on both).  The entire time, I tried setting the AC66U to either AiMesh Node, or it would reboot into Wireless router mode / AiMesh Router mode (default) after the firmware resets.  I remembered seeing a setting that said “Access Point(AP) mode / AiMesh Router in AP mode” on the Operation Mode screen.  One of the problems I noticed in using my iPhone/iPad to connect to the AC66U after it would reboot is that the web UI wouldn’t always load completely, or the router would act like it disconnected when I would get 3/4 of the way through the wizard to set it into AiMesh node mode.  I figured if I switched it into the AP mode (with a wired LAN connection from my switch to the WAN port on the ACC66U), I could use my main PC’s browser to walk it through the setup.

First time through, no luck.  What ended up working was this sequence:

  1. Disconnect the LAN cable and connect to the AC66U via wireless.
  2. Go into Administration->Restore/Save/Upload.  Pick the Restore (not Initialize) option the AC66U to set it back to the “factory” settings after firmware upgrade.
  3. Reconnect to the AC66U via wireless, go into Administration -> Operation Mode. (I frequently would get a partial load here with just a “Save” button.  If you click save, you get a response that says something like “The mode you are in is already the default mode”. Using the ASUS iphone app, just click the refresh icon at the top of the app once or twice and you’ll get the full screen.
  4. Switch the AC66U into Access Point(AP) mode / AiMesh Router in AP mode.
  5. Follow the wizard that asks if you want to get the IP Automatically or manually (I picked Automatic), I think there was one other prompt and then a progress bar that goes from 0-100%. The router will reboot at some point here (the progress bar runs on the phone, not the router itself).
  6. Once it has rebooted, connect back to the GT-5300 and get the IP for the AC66U. In my case, I had already setup a DHCP reservation so that it wouldn’t bounce around on me.
  7. Open a new tab on your web browser and connect to the IP of the AC66U.
  8. Log into the web app and again go to Administration -> Operation mode.
  9. Select AiMesh Node and follow the wizard.
  10. Once the wizard is complete, UNPLUG THE LAN CABLE!
  11. Let the AC66U reboot and go back into your GT-5300 administration page.
  12. Click on Network Map -> Click on the AiMesh icon.
  13. The AiMesh panel comes up on the right, click SEARCH
  14. The AC66U popped up almost immediately! You then have to click on it and confirm that you want to add it as a Mesh Node.
  15. This time the wizard ran up to around 85% and I got a pop up. Much to my surprise, this time it said it was successful!!  I had to do a double take!
  16. I then unplugged the AC66U, moved it to the other end of the house and plugged it back in.

At first, I thought I would have to move it as it wasn’t able to be found via the ASUS iPhone utility. Mesh Nodes still sat at 0 for a while, and then when it did finally pop up and updated to (1) Mesh Node, I clicked on it for status and got a message that it couldn’t communicate with the parent router.  Around an hour later, I was able to connect and we now have several devices that are on it instead of the GT-5300.

Hopefully that’ll save someone else 6 hours of troubleshooting.