RT-AX92u manual settings for stable wireless connection

Hi all,
I want to start a thread to discuss manual settings on the RT-AX92u, which could help with using your pair of routers with a stable wireless connection in your house.
In AiMesh mode on firmwareversion 3.0.0.4.384.7977 I was suffering many crashes, where the log suddenly filled up with memory buffer errors. (My record was over 2000 messages within 5 seconds)
However since the routers worked very good in between crashes and since the pair was good value for money at 330 euro I decided to give them a final try and configure them manually.

• Current high level setup:

VDSL2 modem connection with provider -cable connection PPPOE- RT-AX92 router (RTR) <wireless connection>RT-AX92 repeater(RPT)
I live in a rural area, with limited wifi congestion in the neighbourhood. The router is centrally located in my house, the repeater is 10-15 meters away and there is a thick brick wall in between them.

• wifi setup

• Wireless settings 5Ghz-2
  • RTR:
    • SSID : myconn_dwb
      
    • wireless mode : ax - only
    • WIFI6 mode enable
    • Wifi Agile multiband enable
    • Target wake time : enable
    • Channel bandwidth : 20/40/80 MHZ
    • Control channel : Auto
    • Protected management frames : capable
  • RPT:
    • SSID (managed through network map System Status (right upper side of your config screen) : myconn_dwb
      
    • Roaming assistant disable
    • OFDMA : Enable

• Wireless settings 5Ghz-1

• RTR:
  • enable smart connect : disabled
    
  • SSID : myconn
    
  • wireless mode : auto
  • Control channel : Auto
    
  • Channel bandwidth : 20 MHZ
  • Protected management frames : capable
• RPT:
  • SSID (managed through network map System Status (right upper side of your config screen) : myconn2
    
  • Roaming assistant enable - lower than -70dBm

• Wireless settings 2.4Ghz

• RTR:
  • Enable smart connect : disabled
  • SSID : myconn
    
  • Wireless mode : auto
  • Control channel : Auto
    
  • Channel bandwidth : 20 MHZ
  • Protected management frames : capable
• RPT:
  • SSID (managed through network map System Status (right upper side of your config screen) : myconn
    
  • Roaming assistant enable - lower than -70dBm

Furthermore I changed the wireless professional settings on RTR as shown in attached image for the 5GHZ-2 band.

Finally I also changed the tx_power on the 5GHZ bands. By default it's at 100 but I put it at 175. (In my country 200 is allowed max for 5 GHZ devices) This setting is only available through ssh.

Conclusion
With the above settings I finally managed to get a stable wireless connection , which allowed me to stream movies within my LAN. When testing my speed to the internet from behind the RPT , the speed is about 5 Mbps slower than performing the same test from directly behind the RTR. For me this is acceptable.

Questions?
Do you see room for improving wireless connection further with manual settings?
Do you obtain better performance through AiMesh?

I never used 7977 firmware long enough to experience a crash. I'm staying on 6436 for the the last two months and never had to reboot because of the crash...

My set up is almost the same, apart from that I don't use WAN.

You do need to identify where (which band) the problem is - just randomly modifying settings for all will not get you the performance and stability.

For example I never had issues with the backhaul (wifi6 band) and I have quite large LAN network behind second AIMesh node. But I have numerous issues with both speed and stability of first 5Ghz band...

Also some good starting settings could be found here: https://www.snbforums.com/threads/asus-ax6100-two-ax-92u-routers.61695/

someuser08 said:

I never used 7977 firmware long enough to experience a crash. I'm staying on 6436 for the the last two months and never had to reboot because of the crash...

My set up is almost the same, apart from that I don't use WAN.

You do need to identify where (which band) the problem is - just randomly modifying settings for all will not get you the performance and stability.

For example I never had issues with the backhaul (wifi6 band) and I have quite large LAN network behind second AIMesh node. But I have numerous issues with both speed and stability of first 5Ghz band...

Click to expand...

Yeah these are the settings that worked for me. At first it was rather random, but after a while I start looking up some info on the settings on the wireless-professional tab. (e.g. routerguide.net was very helpful) Based on kind of issues I had, I started toying around with the settings that had an impact on these.

Regarding the crashes, these were I believe more of a router issue than an issue with one of the bands.
Symptoms were sudden loss of WAN connection , while wifi kept working and only solution was rebooting the router manually.
When going through the log there were all these 'runner_get_pkt_from_ring:L137 Failed to allocate new ring buffer'.

someuser08 said:

Also some good starting settings could be found here: https://www.snbforums.com/threads/asus-ax6100-two-ax-92u-routers.61695/

Click to expand...

Hi, thanks for the tip! I went through the suggestions, however disabling a feature (mu-mimo - ofdma) 'because you don't believe the hype' seems rather random. One of these features (ofdma) is available as from the latest version of the firmware, but I believe it was disabled by default

If you just use third band for backhaul connection (one client effectively) there is no point in mu-mimo being enabled...

WJJP said:

Yeah these are the settings that worked for me. At first it was rather random, but after a while I start looking up some info on the settings on the wireless-professional tab. (e.g. routerguide.net was very helpful) Based on kind of issues I had, I started toying around with the settings that had an impact on these.

Regarding the crashes, these were I believe more of a router issue than an issue with one of the bands.
Symptoms were sudden loss of WAN connection , while wifi kept working and only solution was rebooting the router manually.
When going through the log there were all these 'runner_get_pkt_from_ring:L137 Failed to allocate new ring buffer'.

Click to expand...

If you read this forum WAN issues are very common with the latest firmware (ax92u is not much discussed, ax88u is). Everyone who rolled back to 6436 reported the issue going away.

As for your settings - if by reducing channel width(to 25% for 5ghz) and increasing power you get stable connection - that just means you have very saturated local WiFi space. If its just wall thickness, then probably just the power would do...

Thanks for additional input
Based on my findings I would say the automatic settings of AiMesh and smart connect combined are causing issues on both old and new firmware. Only with the latest it ended up crashing the RTR, but a router log filled with wifi devices authenticating, associating and disassociating is something that points to an issue according to me.

To test your hypothesis of I did some tests on channel width and impact on link speed. For the 5Ghz-2 band I obtained following results (keeping all other settings stable)
@ 20Mhz, the link speed dropped to 30 mbps
@ 40 mhz it ended up @ 260 mbps
@ 80 mhz it ended up @ 612 mbps
@ 160 mhz it ended up @ 650 mbps
(side note : in my first post I used 20/40/80 and had higher link speed. I suspect someone moved the RTR slightly inbetween that moment and the moment of writing this post, since it was just on the floor at that point)
Wifi congestion is not an issue, since the only networks shown on my WifiAnalyzer are my own and all of them are nicely spread over the spectrum of the 5 Ghz band. (I live in a rural area)
After running above tests I did one additional change : I moved the RTR from the floor onto a shelf . The RTR moved at max. one meter further and ended up at approx 1m20 height. With previous settings and new location I ended up at 972 Mbps, RSSI slightly worse @ -72dBm
In the end it seems that when facing a challenging wifi environment, you can still improve link speed a lot by just slightly altering location.

someuser08 said:

If you just use third band for backhaul connection (one client effectively) there is no point in mu-mimo being enabled...

Click to expand...

To test this, I disabled MU-MIMO on the 5GHZ-2 band and I was unable to make a connection with the RTR. My guess is that I really need the multiple antennas to send/receive to get through the wall and cover the distance.

update March 1 2020:

• Decided to split 2.4Ghz and 5 Ghz band in two separate networks, which works even better, since you now have control over which band you connect to.
• Dropped the txpower to 150 for the 5GHZ bands and connection remains stable. (At the default of 100 , I couldn't use the 5 Ghz band from everywhere in the house.)
• Noticed that even though the webGUI doesn't show all options for all the bands (RTR and RPT), they still can be enabled through SSH :
  • mumimo for 5GHz-1 band was enabled by default
    
  • ofdma was enabled for both 2.4 and 5 Ghz-1, while in the GUI this option is only available under the 5Ghz-2 band
• Something that went against my expectations was that settings of the RPT didn't always follow the similar setting on the RTR, even though you cannot verify this in the webGUI (you don't have professional tab under wireless in RPT.) I 'synced' my RPT settings with RTR through SSH, to be sure and it feels at least more predictable now.
  • Two settings which I found to be not in sync were airtime fairness and implicit beamforming. While both were disabled on the RTR, on the RPT they were enabled.

I don't know, I just got mine and have been fooling around with them for the last couple of hours, I haven't been able to get much better than 480/600 with them sitting right next to each other.

The best link rate I can get is ~1900Mbps RSSI: -16dBm

What am I doing wrong?

Edit: I changed the wifi6 channel to 100/104 and the connection rate is better but in the bedroom I'm getting no faster (actually a bit slower) than my previous AC86u-Linksys wrt3200acm bridge setup.

Link rate: 3629.6 Mbps
RSSI: -47 dBm

I'm not impressed. I think I just wasted $300.

Hi, hard too see what's going on without more information.
Can you provide an overview of both setups? (e.g. is it internet-ax92-ax92 vs. internet-linksys-ac86u or...) How far are the second units removed from the bedroom? Can you put a number on the actual speed for both setups? (e.g. from speedtest.net or similar sites)
Firmware version of AX92u? AiMesh or manual settings? If manual, can you provide the exact settings you use?
Since both models are from Asus, you can maybe copy paste wireless logs in here for comparison purposes?

WJJP said:

Hi, hard too see what's going on without more information.
Can you provide an overview of both setups? (e.g. is it internet-ax92-ax92 vs. internet-linksys-ac86u or...) How far are the second units removed from the bedroom? Can you put a number on the actual speed for both setups? (e.g. from speedtest.net or similar sites)
Firmware version of AX92u? AiMesh or manual settings? If manual, can you provide the exact settings you use?
Since both models are from Asus, you can maybe copy paste wireless logs in here for comparison purposes?

Click to expand...

I actually have fooled around with multiple configs based on the suggestions made in the forum. I had the ac86u as the base and used the wrt32000 in wireless bridge mode (it was unstable as the main router) and averaged ~400Mbps both ways with the 3200acm in my bedroom. Now I’m getting ~300Mbps with ax on the 92u no matter how I set it up, repeater, bridge, AiMesh, whatever. The 86u is wifi5 and shares the bandwidth with other 5GHz devices so it should be less. I updated both to the recent firmware.

I think the bandwidth might just be too congested around here to get a good connection. Apartment building with multiple unit dwellings all around.

You’re right AiMesh is totally unstable- really doesn’t work at all. I might return it based on that alone. I would try an XT8 but after this I don’t think I’ll do any better with it- I might have to wait for wifi6e.

I’ll post more detailed info later.

Edit- The wifi6 band crashed on the node as I was transferring a small file. It’s not returning even after multiple reboots. I think I’m going to return it.

When using repeater mode, make sure the repeater use same values as main RTR for similar settings. I noticed that this wasn't always the case. Connect through SSH to the repeater.
Working with different ssid for different bands ensures you can select the highest speed band. To see link rate per device, look in wireless log

WJJP said:

When using repeater mode, make sure the repeater use same values as main RTR for similar settings. I noticed that this wasn't always the case. Connect through SSH to the repeater.
Working with different ssid for different bands ensures you can select the highest speed band. To see link rate per device, look in wireless log

Click to expand...

I did. I think one of the 2 I got is a bad one, the fact I had to factory reset to get wifi6 back right off the bat does not lead to much confidence. It’s probably just a return Newegg labeled as “refurbished” I’m just going to send it back and call it a wash-p.

Just to throw this in if you haven't seen me post on the other AX92 thread. I've had constant router hangs with the AX92s. To diagnose I removed the mesh node so I had just one AX92 by itself. I turned off everything I could and it still hung with ring buffer messages in the logs. So that rules out a lot of the things that you guys have been talking about. Unfortunately we need clarity from Asus on this because I've been tormented by it for 6 months now and am ready to throw them in the bin.

Derek Clarkson said:

Just to throw this in if you haven't seen me post on the other AX92 thread. I've had constant router hangs with the AX92s. To diagnose I removed the mesh node so I had just one AX92 by itself. I turned off everything I could and it still hung with ring buffer messages in the logs. So that rules out a lot of the things that you guys have been talking about. Unfortunately we need clarity from Asus on this because I've been tormented by it for 6 months now and am ready to throw them in the bin.

Click to expand...

Removing a node does not change any settings on your device per se I believe.
Do you have smart connect enabled under wireless settings? Can you maybe post extract of your General log which shows a short time before the ring buffers start?
Can you tell us what traffic is going on when the device crashes? (just surfing, streaming video, streaming high quality video) What kind of devices are connected? Anyway without any further info, I would say disable smart connect and start from there.

WJJP said:

Removing a node does not change any settings on your device per se I believe.
Do you have smart connect enabled under wireless settings? Can you maybe post extract of your General log which shows a short time before the ring buffers start?
Can you tell us what traffic is going on when the device crashes? (just surfing, streaming video, streaming high quality video) What kind of devices are connected? Anyway without any further info, I would say disable smart connect and start from there.

Click to expand...

I actually did a full factory reset when I dropped back to a single router. The goal was to simplify everything to try and definitively figure out what the problem is.

Here's what I saw the last time I managed to log in when the router was hung:

Mar 22 20:47:23 wlceventd: wlceventd_proc_event(527): eth5: Assoc 8C:85:90:0C:B1:E3, status: Successful (0)
Mar 22 20:47:27 wlceventd: wlceventd_proc_event(464): eth5: Deauth_ind 8C:85:90:0C:B1:E3, status: 0, reason: Deauthenticated because sending station is leaving (or has left) IBSS or ESS (3)
Mar 22 20:47:35 wlceventd: wlceventd_proc_event(527): eth7: Assoc 8C:85:90:0C:B1:E3, status: Successful (0)
Mar 22 20:51:44 kernel: runner_get_pkt_from_ring:L137 Failed to allocate new ring buffer.
Mar 22 20:51:44 kernel: runner_get_pkt_from_ring:L137 Failed to allocate new ring buffer.

Using top I general see either one or both of the wfd0-thrd and wfd1-thrd tasks maxing out, taking 50% of CPU each. These tasks are associated with the 2.4Gz and 5-1Ghz wifi from what I can figure out.

And just to be clear : This is on a single AX92 that's been factory reset. So AIMesh is not involved or are there any other routers in the network. It could be a device that's talking to the router, but I've got nothing that utilises both bands.

@Derek Clarkson, what did you do after the full factory reset? What changes did you make and how did you make them?

L&LD said:

@Derek Clarkson, what did you do after the full factory reset? What changes did you make and how did you make them?

Click to expand...

Nothing I would consider out of the ordinary. Setup static IPs, ports, etc.

I think Ive tried just about every setting people have talked about on and off and nothing has made any difference.

At the moment I can think of two possibilities: 1. Fundamental bug in the AX92 firmware, and 2: At least two or more devices in my network that are somehow upsetting the AX92. This is based on the fact that both the 2.4Ghz and 5Hz wifis go crazy.


Sent from my iPad using Tapatalk