Is there an app that can notify you if the Wi-Fi channel changes?

[Qbcd]

My RT-AX86U a few times a year will switch from its DFS channel to channel 36, I am fairly certain it's a false positive because it only happens once every 3-4 months. Unfortunately the router doesn't offer the option to automatically switch back after a certain period of time, which is annoying.

I eventually discover it and fix it, but I was thinking, is there an app that can notify you if the 5 GHz or 2.4 GHz channel changes? Or at least display the channel in the notifications? I know there are many network analysis apps that will show you channel and a whole bunch of other network data, but I don't need any of that, I don't want to have to open an app and go into a separate screen and look at a graph, etc. I want it to be instantly accessible or preferably a notification.

Please let me know if you know of such a thing, thanks!

 

[B255ea006]

My RT-AX86U a few times a year will switch from its DFS channel to channel 36, I am fairly certain it's a false positive because it only happens once every 3-4 months. Unfortunately the router doesn't offer the option to automatically switch back after a certain period of time, which is annoying.

I eventually discover it and fix it, but I was thinking, is there an app that can notify you if the 5 GHz or 2.4 GHz channel changes? Or at least display the channel in the notifications? I know there are many network analysis apps that will show you channel and a whole bunch of other network data, but I don't need any of that, I don't want to have to open an app and go into a separate screen and look at a graph, etc. I want it to be instantly accessible or preferably a notification.

Please let me know if you know of such a thing, thanks!

Hi,

wow an app regarding the actua Wi-Fi channel. That is pretty deep and i do not see how that would help you anyways.
I would understand if you would as for a browser extension which notifies about the IP to be aware of the actually working VPN setup.

I am sorry i do not know about an app like you are asking for.

Regards

 

[sfx2000]

My RT-AX86U a few times a year will switch from its DFS channel to channel 36, I am fairly certain it's a false positive because it only happens once every 3-4 months. Unfortunately the router doesn't offer the option to automatically switch back after a certain period of time, which is annoyin

Asus has their mobile app - sounds like a reasonable enhancement request to the team there...

 

[To the ocean]

Yap, maybe you can feedback through the ASUS Router APP to make a wish to the ASUS team

 

[drinkingbird]

My RT-AX86U a few times a year will switch from its DFS channel to channel 36, I am fairly certain it's a false positive because it only happens once every 3-4 months. Unfortunately the router doesn't offer the option to automatically switch back after a certain period of time, which is annoying.

I eventually discover it and fix it, but I was thinking, is there an app that can notify you if the 5 GHz or 2.4 GHz channel changes? Or at least display the channel in the notifications? I know there are many network analysis apps that will show you channel and a whole bunch of other network data, but I don't need any of that, I don't want to have to open an app and go into a separate screen and look at a graph, etc. I want it to be instantly accessible or preferably a notification.

Please let me know if you know of such a thing, thanks!

Maybe set up a syslog server, I'm assuming it logs something, then you could set an alert on that log message to text or email you.

Or just set your router to reboot every night at like 3AM. Worst case, you have a partial day with lower throughput.

 

[Matthew Patrick]

It might be possible with cronjob right? Cron will run a script which will check the current channel which is stored in nvram I think. Then send a telegram message if it matches what you want. But I think you need Merlin firmware for that

Edit :
Yes it is stored in the nvram

 

[Qbcd]

Maybe set up a syslog server, I'm assuming it logs something, then you could set an alert on that log message to text or email you.

Or just set your router to reboot every night at like 3AM. Worst case, you have a partial day with lower throughput.

Weirdly no, I can never find any mention of the channel change in the log.

I think I'll put a request in the Asus app. In Windows command prompt, I can use a command line that tells me the channel (even if I'm not connected to Wi-Fi), maybe I can set up some kind of a script in Windows that runs the command once a day and if it detects a certain number or lack of a certain number, it alerts me. I have no idea how to do any of that though.

 

[Adooni]

can you tell why you are using DFS channel - is normal not available/ crowed etc?
here you can read Asus definition for it https://www.asus.com/support/FAQ/1045936/ and you can find a reason to avoid those

my friend was using DFS channel and he is close to east Poland border and because of "russian sick person" we have a much more military movements and radars were the reason he was loosing wi-fi connection for few minutes even.

for android you have very nice app called wi-fi analyzer and I always check what channels are occulated and just set fixed one - do not see a reason to put this on auto.
In my building I have got 50+ wi-fi and no issue to find one channel that is free and have good wi-fi connection.

 

[drinkingbird]

can you tell why you are using DFS channel - is normal not available/ crowed etc?
here you can read Asus definition for it https://www.asus.com/support/FAQ/1045936/ and you can find a reason to avoid those

my friend was using DFS channel and he is close to east Poland border and because of "russian sick person" we have a much more military movements and radars were the reason he was loosing wi-fi connection for few minutes even.

for android you have very nice app called wi-fi analyzer and I always check what channels are occulated and just set fixed one - do not see a reason to put this on auto.
In my building I have got 50+ wi-fi and no issue to find one channel that is free and have good wi-fi connection.

If you use 160Mhz you can't avoid DFS. Well if your router and all clients support 80+80 mode you can but I don't think Asus does.

 

[dev_null]

@ColinTaylor 's script will check and restart wifi if the channel changes: https://www.snbforums.com/threads/rt-ax86u-doesnt-switch-back-to-dfs-channel.77728/post-784233

I extended it to include email notification based on the original email approach I developed for dn-vnstat v1, but it's a bit of a hack, and honestly re-setting wifi to get me back to my original channel is enough. But happy to share my hack if interested.

 

[Qbcd]

can you tell why you are using DFS channel - is normal not available/ crowed etc?
here you can read Asus definition for it https://www.asus.com/support/FAQ/1045936/ and you can find a reason to avoid those

my friend was using DFS channel and he is close to east Poland border and because of "russian sick person" we have a much more military movements and radars were the reason he was loosing wi-fi connection for few minutes even.

for android you have very nice app called wi-fi analyzer and I always check what channels are occulated and just set fixed one - do not see a reason to put this on auto.
In my building I have got 50+ wi-fi and no issue to find one channel that is free and have good wi-fi connection.

There's always someone who asks why use a DFS channel when a DFS-related question comes up. But fair enough, yes it's because the non-DFS 80 MHz channel (36-52) has several other APs in the area, whereas the DFS channels are completely clear. Also, where I am channels 100-140 have a significantly higher legal power limit of 1W, which makes a big difference for my mesh network.

I don't live near radar or an airport, so the router only switches to channel 36 a few times a year, roughly once every 3 months and I am almost certain it's false positives or something else entirely that causes the channel to reset. I never see DFS or radar mentioned in the log when it happens or any indication of channel switching in the log, so I think it's a glitch.

The other reason I think it's a glitch is that if I turn on a guest network, then it happens A LOT more, roughly once every 2-3 days it'll switch back to channel 36 from channel 100. So there's something there that causes the channel to reset, I've sent Asus a note about it...

 

[Qbcd]

@ColinTaylor 's script will check and restart wifi if the channel changes: https://www.snbforums.com/threads/rt-ax86u-doesnt-switch-back-to-dfs-channel.77728/post-784233

I extended it to include email notification based on the original email approach I developed for dn-vnstat v1, but it's a bit of a hack, and honestly re-setting wifi to get me back to my original channel is enough. But happy to share my hack if interested.

This is cool, but I don't really want to mess with Merlin. I've given up trying to switch the channel back automatically, I'm fine with just being notified since it only happens a few times a year. This script also fully resets the router, which is less than ideal, and I'd rather have control over when that happens.

What I'm looking for is some way to execute a batch file in Windows daily (I know how to do that part), and then look at the result and if a certain string is found or not found then notify me.

That way I can just do "netsh wlan show networks mode=bssid | findstr /I /R "100" in command prompt which will return some "Channel 100" lines if it detects a network on Channel 100 (mine is the only one), or it'll return nothing if there's nothing on channel 100. And then notify me in Windows if it doesn't see the number "100" in the result for instance. But how do I do that... is what I'm researching right now, hoping to find an easy solution. If anyone has any ideas please share.

 

[Matthew Patrick]

This is cool, but I don't really want to mess with Merlin. I've given up trying to switch the channel back automatically, I'm fine with just being notified since it only happens a few times a year. This script also fully resets the router, which is less than ideal, and I'd rather have control over when that happens.

What I'm looking for is some way to execute a batch file in Windows daily (I know how to do that part), and then look at the result and if a certain string is found or not found then notify me.

That way I can just do "netsh wlan show networks mode=bssid | findstr /I /R "100" in command prompt which will return some "Channel 100" lines if it detects a network on Channel 100 (mine is the only one), or it'll return nothing if there's nothing on channel 100. And then notify me in Windows if it doesn't see the number "100" in the result for instance. But how do I do that... is what I'm researching right now, hoping to find an easy solution. If anyone has any ideas please share.

As I said before. If you're on Merlin you can make it run a script every few minutes to check the current channel using nvram command. Then you should be able to use if else then notify you via telegram.

It might be possible with cronjob right? Cron will run a script which will check the current channel which is stored in nvram I think. Then send a telegram message if it matches what you want. But I think you need Merlin firmware for that

Edit :
Yes it is stored in the nvram
View attachment 46798

 

[dev_null]

This is cool, but I don't really want to mess with Merlin. I've given up trying to switch the channel back automatically, I'm fine with just being notified since it only happens a few times a year. This script also fully resets the router, which is less than ideal, and I'd rather have control over when that happens.

It does not reset the router. It disables and then re-enables wifi, which would take the wireless connections offline for about 30 seconds for 2.4gHz and up to a few minutes for 5gHz.

If you're worried about this disrupting use during say, working hours, then set up a cron job that checks after working hours, or even in the middle of the night. If your changes are infrequent, that should be sufficient.

Add this to services-start (checks at 20 mins after each hour, between midnight and 6AM and 6PM to 11PM only):

cru a channel_ck "20 0-6,18-23 * * * sh /jffs/scripts/channel-ck.sh" #ColinTaylors check channel and restart

What I'm looking for is some way to execute a batch file in Windows daily (I know how to do that part), and then look at the result and if a certain string is found or not found then notify me.

That way I can just do "netsh wlan show networks mode=bssid | findstr /I /R "100" in command prompt which will return some "Channel 100" lines if it detects a network on Channel 100 (mine is the only one), or it'll return nothing if there's nothing on channel 100. And then notify me in Windows if it doesn't see the number "100" in the result for instance. But how do I do that... is what I'm researching right now, hoping to find an easy solution. If anyone has any ideas please share.

You could hook into amtm email system for email notifications with your script. There's details about that in the dn-vnstat and diversion threads.

If you choose to look for channel change warnings, you're looking specifically for "wl_chanspec_changed_action" in most cases. You'd then need to somehow filter those because the log will contain even older entries until it's reset. I used sed to remove the entries (it worked but I didn't like messing with the live log output).

 

[dev_null]

can you tell why you are using DFS channel - is normal not available/ crowed etc?

I use DFS channels because we moved to a crowded townhouse complex with hundreds of other residents. Even now, there's some spectrum in DFS available (I could go to 160, but don't need the BW for my uses):

(From what I can see, a lot of this is driven by poorly set-up (probably poorly designed) mesh networks. The non-technical residents on either side have mesh networks that are taking up *three different channels each* just to cover a 130m2 flat, which is crazy. My *single* RT-AX86U is positioned on the 2nd floor, centrally and coverage is more than adequate.)

 

[rung]

This is cool, but I don't really want to mess with Merlin. I've given up trying to switch the channel back automatically, I'm fine with just being notified since it only happens a few times a year. This script also fully resets the router, which is less than ideal, and I'd rather have control over when that happens.

What I'm looking for is some way to execute a batch file in Windows daily (I know how to do that part), and then look at the result and if a certain string is found or not found then notify me.

That way I can just do "netsh wlan show networks mode=bssid | findstr /I /R "100" in command prompt which will return some "Channel 100" lines if it detects a network on Channel 100 (mine is the only one), or it'll return nothing if there's nothing on channel 100. And then notify me in Windows if it doesn't see the number "100" in the result for instance. But how do I do that... is what I'm researching right now, hoping to find an easy solution. If anyone has any ideas please share.

I run the following script from Termux on my phone. I am sure you could do something similar from DOS.

~ $ cat wifichan.sh
#!/bin/sh
ssh admin@192.168.1.1 nvram show | grep _sel_
~ $ ./wifichan.sh
size: 73144 bytes (57928 left)
wl0_sel_bw=20
wl0_sel_channel=8
wl0_sel_nctrlsb=0
wl1_sel_bw=160
wl1_sel_channel=100
wl1_sel_nctrlsb=0
~ $