Issue adding AC-68U as AiMesh node

[ewib]

Hi there, I'm a new member to this forum. I have a weird problem with an AC-68U router running Asuswrt Merlin. The router was previously part of an AiMesh system. The main router is an AX-58U running Asuswrt Merlin 386.2_2 (router A). Until yesterday the AC-68U router has been working well in the AiMesh system, running Asuswrt Merlin 386.2_2. There were 4 AiMesh nodes in the system yesterday, all connected via 1G ethernet to the AX-58U. The main router A and 2 of the nodes are running 386.2_2, one is running 386.2_4 and the other 386.2_6.

This morning I tried to add a fifth AC-68U router running Asuswrt Merlin 386.2_6 (router B). This is where the problem starts I believe. The node addition process failed with a message in the main router A: "Unable to add your AiMesh node RT-AC68U (<mac addr>) to your AiMesh system due to the following situations. Please check and try again.". The message continues to list 5 possible reasons for the failure, which have all been ruled out. I thought that an AiMesh node is limited to 4 nodes, so I removed one of the working AC-68U that is running 386.2_2 (router C). I then tried to add router B again, but the problem remains.

After this I tried to add router C back into the AiMesh system. Surprisingly I'm getting the same error message adding this router, when nothing has been done to the router (other than removing it from the AiMesh system earlier). I tried it the second time after resetting the router (using the WPS button procedure), but it failed as well. I then upgraded the firmware to 386.2_6 to see if it solves the problem, but that failed as well.

Thinking that the problem might be in the main router A I then rebooted the AiMesh system, which I believe should have rebooted the main router and the 3 existing AiMesh nodes. Once everything is back up and running I tried adding router C back into the system (still running 386.2_6), but the process failed with the exact same message in the main router A.

I have not tried (mostly because I don't want to disturb an otherwise working system) to sync up the firmware of the main router and the 3 existing nodes to 386.2_6.

Does anyone know how to resolve this issue? Any help would be greatly appreciated!

 

[L&LD]

For a stable AiMesh system, being on the same (latest) firmware is essential. Too many permutations of weird stuff can happen when you're trying to mix and match.

Fyi, the latest RMerlin Alpha versions (VPN Director testing) have fixed a multitude of issues and long-standing bugs and seem very stable to me in my network, and a few select customers networks too.

Download | Asuswrt-Merlin

How big is the area you're trying to cover with 5 routers? How are nodes placed and connected?

You may want to physically unplug all the routers, wait at least 5 minutes, and then starting with the main router, plug each one back in one by one (this works better than an AiMesh Reboot command).

 

[ewib]

Hi, thanks for your suggestions! I'm trying to solve a few weak spots in my house and front/back yard. The main router is buried deep in the basement storage room that is nearly full of stuff. There is 1 node in the basement, 2 nodes in opposite ends of the main floor, and 1 node in the second floor.

I will try your second suggestion very soon, but I suspect it has to do with the various firmware versions in the system. To synchronize the firmware version should I start by upgrading the main router? Do I need to remove all the nodes before upgrading the main router, just turn them all off, or keep them running?

 

[L&LD]

How are the nodes connected? Wired or wireless? How many SqFt are you trying to cover?

When was the last time you performed a full reset of the network?

If you're going to try the Alpha, disconnect everything from the wall power and start with the main router.

Upgrade the firmware first, perform a full reset to factory defaults using the WPS method appropriate for each model, then do a minimal and manual configuration on the main router.

Upgrade each node to the same firmware level and perform the same WPS appropriate reset. Then, add and test each node as you go.

 

[ewib]

I tried the second method. I turned everything off, waited 5 mins, turned main router A on and waited until it's back online, turned router C on and tried to add it back to the AiMesh systrm once it's online (with all the other nodes still off), and the process failed the same way. The addition process seemed to progress at the normal rate until progress percentage hit 35, and then it seemed to hit the failure point, progress percentage zoomed to 100 and the error message displayed right after.

 

[ewib]

The answers to your first set of questions are in my original and second post.
1. All the nodes are connected to the main router via wired 1G ethernet backhaul.
2. House is about 3300 sq ft. Since all nodes and the new router use 1G ethernet backhaul I believe house size is not the cause of the issue.
3. I did whole system reboot this morning.

Is it absolutely necessary to restore the main router to factory default after its firmware is upgraded?

 

[jsbeddow]

I tried the second method. I turned everything off, waited 5 mins, turned main router A on and waited until it's back online, turned router C on and tried to add it back to the AiMesh systrm once it's online (with all the other nodes still off), and the process failed the same way. The addition process seemed to progress at the normal rate until progress percentage hit 35, and then it seemed to hit the failure point, progress percentage zoomed to 100 and the error message displayed right after.

Yes, but did you do the full WPS button reset on the node(s) and main router after updating the firmware on each? Yes, it is essential if you want the best chance of a stable system.

 

[jsbeddow]

Truth be told, you may never achieve a stable AiMesh with your (wireless) nodes being RT-AC68U units: others may have a different opinion, but I know my setup couldn't be stable in this manner, even after weeks of troubleshooting. It may seem ok for days, up to a couple of weeks, but mine would always crash (lose internet connection) eventually, requiring a reboot of the node. The only truly stable configuration was using the RT-AC68U as a media bridge: even using it as a wireless repeater suffers from the same eventual crash (it might go up to a few weeks before this happens, though). I know others have seen the same thing with this model as a node, so I can only conclude that despite this being the Asus "workhorse/reliable" model in general, something about it is wonky as a wireless node (whether through AiMesh or manual setup as a wireless repeater).
One odd bug of note here: when setting up this model as a wireless repeater, it will always display as an "open system" on the main (index) page, despite most definitely using WPA2 encryption. Yet another quirk/bug....

 

[cofetym]

Try a different browser and if you can consider AP mode for your extra routers,

 

[bbunge]

I, too, have had problems adding an AC68U to a mesh system. Ironically it had another AC68U as a main router!

Suggestions: on your main router, AX58U, set separate SSID's for 2.4 and 5 GHz, use WPA2, used fixed non-DFS channels and bandwidth for 2.4 and 5 GHz. Make sure WPS is enabled on the AX58U. You do not need Merlin on the nodes but the firmware, even if Asus, needs to be up to date.
If you can not add the node via WIFI with the node in the same room as the router, connect an Ethernet patch cable from the router LAN port to the node WAN port then hard factory reset the node (https://www.asus.com/support/FAQ/1039074/) and after the node starts up try to add the node again. Once it is added you can power the node down and move it to the desired location. Oh, do not turn on Ethernet backhaul only on the router until all the nodes are added. I had to try to add the stubborn node several times but it is now over two months of successful operation.

 

[jsbeddow]

I, too, have had problems adding an AC68U to a mesh system. Ironically it had another AC68U as a main router!

Suggestions: on your main router, AX58U, set separate SSID's for 2.4 and 5 GHz, use WPA2, used fixed non-DFS channels and bandwidth for 2.4 and 5 GHz. Make sure WPS is enabled on the AX58U. You do not need Merlin on the nodes but the firmware, even if Asus, needs to be up to date.
If you can not add the node via WIFI with the node in the same room as the router, connect an Ethernet patch cable from the router LAN port to the node WAN port then hard factory reset the node (https://www.asus.com/support/FAQ/1039074/) and after the node starts up try to add the node again. Once it is added you can power the node down and move it to the desired location. Oh, do not turn on Ethernet backhaul only on the router until all the nodes are added. I had to try to add the stubborn node several times but it is now over two months of successful operation.

I am curious @bbunge, did you leave WPS enabled "permanently" ? I am aware it needs to be on initially when setting up AiMesh, but I would always go back and turn it off after setting this up. Maybe the source of my troubles, but I still recall that WPS was/is considered a security risk.

 

[ewib]

Thanks for all the advice! I'll upgrade the firmware to 386.2_6 tomorrow morning when no one is using the network.

For the main router, would I get the benefit of resetting to factory default if I save the router's settings before upgrading and restore these settings after upgrading and resetting to factory default? I'm guessing the answer is no, but since this can save me a lot of time I'd like to know for sure.

 

[L&LD]

Only 3,300 SqFt? I think you're oversaturating your Wi-Fi environment.

If you haven't done the WPS reset appropriate for your main router recently, the following link may help. Do not import any saved config files. Do not 'blindly' use old settings, scripts, or features that 'once worked'.

Fully Reset Router and Network

The link below suggests what is commonly believed to be best practices today.

Best Practice Update/Setup Router/AiMesh Node(s) 2021

 

[bbunge]

Thanks for all the advice! I'll upgrade the firmware to 386.2_6 tomorrow morning when no one is using the network.

For the main router, would I get the benefit of resetting to factory default if I save the router's settings before upgrading and restore these settings after upgrading and resetting to factory default? I'm guessing the answer is no, but since this can save me a lot of time I'd like to know for sure.

The answer to use the old settings is no. There is no real reason to reset the main router. Just try to add the node after it is given a hard factory reset.

Yes, I have left WPS enabled. I manage the network remotely and I just have not turned it off.

See my link above for the "official Asus Hard Factory Reset" instructions. Just starting with the WPS pressed is not the full answer as some think.

 

[jesteves]

I am with the same problem…

Trying to add a AC-68u as Aimesh node to my AC-88u, and always fails at 35%…
Both routers with 386.2_6 firmwares, and all reseted to factory defaults.

For now i give up trying and put my AC68u in Repeater Mode (works excellent)

 

[csj97229]

I ran into this a couple of weeks ago when trying to add an RT-AC68U (running 386.2_6) as an AI-Mesh node for an RT-AC86U router (also running 386.2_6). I spent way too much time trying to get them to pair up, each time failing at around 35%, before finally running a physical cable as "bbunge" recommends above. That allowed the new device to be added as a node. After that I had to tweak some settings on the router to tell it I didn't want to use the wired backhaul connection, which seemed to be more challenging than I thought it needed to be. Since then the AI-Mesh node has been working fine from the other side of the property using wireless backhaul.

 

[ewib]

Just reporting back that the cause for the issue I experienced was an ethernet switch in between the router I tried to setup as a node and the main router. Once I bypassed the switch the problem was resolved.

I did proceed with upgrading the system to 386.2_6 and it is stable now. However, I noticed a slight difference in that if I try to bind an active device (my phone) to any node it always says that the signal was too weak, but it is ultimately successful and the signal is good. I have never experienced this issue with 386.2_2.