Asus Zenwifi XT8 5GHz-2 Band DFS Channel Backhaul Behavior

[tomatopotatochilli]

That's weird, if not a DFS channel, maybe a bad unit. Try factory reset, else return/exchange.

I can confirm that doesn't happen for me. I assuming you are on latest firmware. Mine is below.

 

[JoWa]

That's weird, if not a DFS channel, maybe a bad unit. Try factory reset, else return/exchange.

I can confirm that doesn't happen for me. I assuming you are on latest firmware. Mine is below.

View attachment 26157

Correct, I also use the 25524 fw. also tried the RC2 and all the way back to the first official release... but its maybe like you say.. a bad unit.

 

[tomatopotatochilli]

It is Asus aggressive DFS implementation.

If you want to test it then turn your router off then back on again and look in the wireless log.

Alternative is to manually pick each channel one by one and it will trigger this in the wireless log.
View attachment 26132

I didn't fully understand your point of testing/simulating a DFS event. Here's my log just after a reboot. What to make of it?

 

[JagoUK]

I didn't fully understand your point of testing/simulating a DFS event. Here's my log just after a reboot. What to make of it?


View attachment 26158

Well according to that you have a damn site more channels available that what UK is restricted to. And none are showing as having an event in the past half hour. You are getting 160mhz so all is fine as far as DFS is concerned.

Could still check event log for "Radar"

 

[tomatopotatochilli]

Yes, DFS events are not happening frequently at all. I wonder if they can still happen sometimes and there a 2 minute loss of connectivity can make my family frown on the fancy high speed setup.

 

[JagoUK]

A Radar detect will look like this in your system log. But it doesn't always list it which I think is a bug.

Aug 4 04:30:53 wlceventd: wlceventd_proc_event(632): eth6: Radar detected

 

[tomatopotatochilli]

Couldn't find radar/dfs keyword in the log.

 

[JoWa]

Im hoping for the best here. Tested rc5, but reverted back to official 25524 as rc5 was giving me slower wifi speed. I have 250mbit but was only getting 160mbit with rc5.

So, I did a new install with official, I switched place router and nod, so nod became router instead. Left almost every setting untouched, except ssid, Qos and roaming butt for backhaul 5-2 where I put -90 instead of original -70. According to my asus app, I'm on -52 so I do have a great signal strength.

And for the first time since I bought this pair of xt8 over 2 month ago, it has not dropped the 5ghz uplink til 2,4 for 18 fukking hours now

 

[tomatopotatochilli]

Thanks JagoUK for all the help, looks like DFS events are not an issue in my location.

Here's my setup (stable over last couple days) for now.

Wireless AiMesh backhaul. QoS off, Smart Connect off, Roaming assistant off, Wifi Agile Multiband On in 5.1 and 5.2 bands.

Notes:

1. Same SSD in all 3 bands. Router won't let me set same SSID in 5.2 so used following commands:

SSH to Main Router
nvram set wl2_ssid="MyHomeSSID"
nvram commit
Wait 30 seconds, reboot all nodes.

2. This open up entire 600 + 1200 + 4800 Mbps bands for my devices to share.

3. My hope with same SSID is that if 5.1/5.2 go offline, devices will naturally switch to 2.4 (same ssid) and stay connected even at lower speeds. When the 5.1/5.2 come online (automatic or manual intervention), again devices will just go to that. Simpler setup for my client devices.

4. Windows devices used the driver settings I mentioned earlier to Prefer 5 GHz band and Roam aggressively. They are connecting almost optimally t the right band/AP. Phones are connecting well, though at times not choosing optimal band/AP but still not bad.

5. Even though I am sharing the 5.2 band for AiMesh and Fronthaul, it is not slowing down things in practice. It is actually allowing my Wifi 6 devices to connect to main router at 2400 Mbps.

6. I have a gigabit WAN connection and I have seen 900+ Mbps on my Wifi 6 device 20 ft away from the router. Yes, it happens.

Hope the setup stays consistently stable and doesn't fall like a house of cards

Comments/critique welcome. If these notes helps anyone, please use them and leave comments.

If any Asus engineer reads this, please first read JagoUK's review and take those suggestions, then add these:

1. Improve DFS switching implementation to not affect 5.1 and use it as a backhaul if you have to switch off 5.2. A normal 5.1 router which is not on DFS channel doesn't get affected by a DFS event, so should XT8 not when not on a DFS channel.

2. Allow 5.2 to be used as Fronthaul in the UI easily in addition to backhaul if the user wants to share that band. Sharing a 4800 Mbps channel with backhaul is still better than a dedicated fronthaul channel of 1200 in many situations.

Thanks.

 

[JoWa]

today, my 5ghz uplink dropped to 2,4.. it lasted for 3 days...

 

[tomatopotatochilli]

Based on JagoUK's instructions, can you check if a DFS/Radar event happened?

If not, do you want to try to set it up with the instructions I gave which switch off a bunch of features like Smart connect, roaming assistant etc.?

 

[JoWa]

Hi, this is my log file. 14.28 is where I think it dropped. That message occurs also later in log file several times.

 

[JoWa]

Based on JagoUK's instructions, can you check if a DFS/Radar event happened?

If not, do you want to try to set it up with the instructions I gave which switch off a bunch of features like Smart connect, roaming assistant etc.?

did you turn off roaming in all 3 band?

 

[tomatopotatochilli]

did you turn off roaming in all 3 band?

I disabled Smart Connect, and Roaming Assistant everywhere. I did enable Wifi Agile Multiband which, in my understand, is the Wifi 6 way of influencing clients to roam.

I have a single SSID and most of the times, the devices are connecting to the right band/AP. See some driver settings in earlier response.

 

[JoWa]

I disabled Smart Connect, and Roaming Assistant everywhere. I did enable Wifi Agile Multiband which, in my understand, is the Wifi 6 way of influencing clients to roam.

I have a single SSID and most of the times, the devices are connecting to the right band/AP. See some driver settings in earlier response.

Why do you enable it if you disable roaming then?

 

[tomatopotatochilli]

What do you mean by disable roaming? Given a mesh system, you want client devices to roam between APs, and choose best bands for the device.

Asus custom solution for that is through SmartConnect and Roaming assistant. I disabled those as they were creating disconnects etc.

The Wifi Standard solution for this is Wifi Agile Multiband, which was disabled by default and I enabled it. Along with driver settings in some devices, it seems to work quite well. Read up on Agile Multiband if you want.

In the end, all being said, it is a trial and error approach though. Try and see if it works.

 

[TBONE204]

What do you mean by disable roaming? Given a mesh system, you want client devices to roam between APs, and choose best bands for the device.

Asus custom solution for that is through SmartConnect and Roaming assistant. I disabled those as they were creating disconnects etc.

The Wifi Standard solution for this is Wifi Agile Multiband, which was disabled by default and I enabled it. Along with driver settings in some devices, it seems to work quite well. Read up on Agile Multiband if you want.

In the end, all being said, it is a trial and error approach though. Try and see if it works.

so WIFI Agile Multiband is the standard accepted by the Wifi Alliance and does the same as SmartConnect and Roaming assistant? so if you disable SC and RA, you should be enabling WAM if you want your devices to still roam between access points?

Does anyone have experience as to which method works more effectively?

thanks

 

[tomatopotatochilli]

My experience was that WAM worked better. Yes, it is part of Wifi standard.

The real issue is routers can only hint or disconnect clients, they really can't force a client to connect to a certain AP/band. In the end it is client code that decides. Some clients/drivers implement these suggestions well, some do it badly and some can be configured.

Even if you disable all these features, some clients will have no trouble roaming. A simple client, that periodically evaluates the APs with good signal for the connected SSID, and then picks the fastest (with band speeds considered) network to join will just do fine.

 

[tomatopotatochilli]

[Wireless Router] What is Wi-Fi Agile Multiband? | Official Support | ASUS USA

" Wi-Fi Alliance released Wi-Fi Agile Multiband for better Wi-Fi coverage and improved connection speed. Different from the roaming features provided by router companies, Wi-Fi Agile Multiband has much better compatibility for IoT devices. "

Wi-Fi Agile Multiband | Wi-Fi Alliance

www.wi-fi.org

" Many device makers and operating systems vendors do employ some of these capabilities. However, Wi-Fi Agile Multiband is standards-based, ensuring interoperability across vendors. "

Worth going over the two links and playing with it in your setup of devices you have. I have personally upgraded 4 existing laptop/PCs in my home with relatively inexpensive Intel AX200 Wifi Cards ($18-$30). My plan is to slowly upgrade phones and such to Wifi 6 over coming years naturally.

 

[JoWa]

Ok, I´ve enabled WAM and turned off all the features like you did. Let see how it goes....