RT-N66U 2.4Ghz drops, but clients can't reconnect

[simon451]

Hi there,

I'm having a very strange issue with my RT-N66U router. I have two separate SSIDs for the 2.4 and 5Ghz bands and am running the latest firmware 3.0.0.4.376.3861. All devices suddenly drop (approx once per day) off the 2.4 band, but the strange thing is they refuse to reconnect. My 5Ghz clients (and a wired client) are fine with no issues. Two of my 2.4Ghz devices act as follows. My Android phone after dropping signal just says "authentication error" and refuses to connect, and my PS4 also sees the network but cannot get an IP address. A reboot of the router fixes things, or just leaving things for a while they eventually reconnect. I haven't really paid attention to how long it takes for them to reconnect as for a while I just put the dropouts down to just general internet drops until now. I've had a good look round the forum to see if it is a common glitch but can't seem to find any mention of it. It has been doing this for about four weeks I'd say, roughly when I last updated the firmware. The only other thing to mention is that I had a similar problem roughly six months ago when I enabled the guest network - exactly the same problem, but disabling the guest network fixed it (guest network has remained off since then).

Any suggestions would be gratefully received,

Many thanks,

Simon

 

[wouterv]

Depending on your router firmware history it may be good to clear the router NVRAM and manual configure the router again, as follows:

Clear NVRAM using Telnet:

1. Advanced Settings>Administration>System: Enable Telnet = Yes
2. Open a Telnet session to the router.
3. Run the following command from the Terminal prompt: mtd-erase -d nvram
4. Power down the router and start it up again.
5. Access the router at the default IP address 192.168.1.1 and admin/admin
6. Manual configure the router again (do NOT load an old configuration backup file).
7. Optional: delete the wireless connection profiles on your computers and connect again.

 

[jlake]

Try basic troubleshooting steps:

http://www.snbforums.com/threads/rt-ac66u-poor-performance-dropping-connections.12453/

And use their wifi analytics tool for interference check:

http://www.ampedwireless.com/wifianalytics/

 

[simon451]

Thanks very much for the replies, much appreciated. I have factory reset the router as suggested and manual configured the router again. I've also deleted any old connection profiles saved on computers as well as changing the SSIDs on the router. Fingers crossed! Thanks again

 

[simon451]

Unfortunately no joy. Same issue last night, 2.4Ghz clients dropped and cannot reconnect. This is very strange, I can understand drops but not the refusal of clients to rejoin the network. I did the factory reset, but I'm not sure if that also clears the NVRAM or not? When I reset the router I just set up the two SSIDs and security but made no other changes. I'm no expert but surely the problem indicates a glitch somewhere in the firmware but resetting everything has not helped, and a good look round this forum and on the internet in general cannot find another single instance of this problem. Any other ideas would be much appreciated?

 

[jlake]

Unfortunately no joy. Same issue last night, 2.4Ghz clients dropped and cannot reconnect. This is very strange, I can understand drops but not the refusal of clients to rejoin the network. I did the factory reset, but I'm not sure if that also clears the NVRAM or not? When I reset the router I just set up the two SSIDs and security but made no other changes. I'm no expert but surely the problem indicates a glitch somewhere in the firmware but resetting everything has not helped, and a good look round this forum and on the internet in general cannot find another single instance of this problem. Any other ideas would be much appreciated?

So you liked some of my troubleshooting steps, but felt the others were unworthy of your time and effort?

 

[simon451]

No, I have tried all of the troubleshooting tips, sorry if I didn't make that clear in my post.

 

[wouterv]

The 2.4GHz clients are they 802.11b, 802.11g, 802.11n or a mix of those?
How is the router configured?
I suggest revert to factory defaults again, and only set as guided by the setup wizard: username/password, SSIDs and wireless security.
Then try again.

 

[simon451]

Thanks for the reply wouterv. All my N clients are on the 5Ghz network with no mix, g clients on the 2.4Ghz and don't have any b clients. Only change to that was on my last test where I added a couple of the N clients to the 2.4 band just to check it wasn't a problem the client end but they too went down.

The normal router setup is minimal, the two SSIDs set up with different names and I believe the only other changes where "Optimized for Xbox" checked and the 2.4 Channel bandwidth set to 20Mhz, but after the reset early last week left those two options to their defaults - Xbox unchecked and Channel Bandwidth set to 20/40Mhz and problem remained.

I'll try another factory reset as you suggested and just set up the basics and let you know how I get on. Thanks again for the help

 

[wouterv]

Thanks for the reply wouterv. All my N clients are on the 5Ghz network with no mix, g clients on the 2.4Ghz and don't have any b clients. Only change to that was on my last test where I added a couple of the N clients to the 2.4 band just to check it wasn't a problem the client end but they too went down.

The normal router setup is minimal, the two SSIDs set up with different names and I believe the only other changes where "Optimized for Xbox" checked and the 2.4 Channel bandwidth set to 20Mhz, but after the reset early last week left those two options to their defaults - Xbox unchecked and Channel Bandwidth set to 20/40Mhz and problem remained.

I'll try another factory reset as you suggested and just set up the basics and let you know how I get on. Thanks again for the help

Ok, lets await your further testing.
The bandwidth setting of 2.4GHz to 20MHz is recommended for crowded areas (which is valid for 95% of the users).
A frequent check of the wireless usage in your neighborhood is strongly recommended, neighbor equipment can come and go, and like my neighbors: they can switch channels ever so often. On 2.4GHz this can be killing for your connections.
If you have no Xbox: leave the setting unchecked.
If you have no 802.11b equipment: unchecked the b/g Protection setting.

 

[simon451]

Thanks wouterv. Will leave the Xbox setting off and uncheck the b/g protection as don't have any b devices. I'm fairly isolated where I live - scanning brings up no other available wireless networks but will keep to 20MHZ as you suggest for the bandwidth in case there is some interference.

 

[bbunge]

May sound strange but look for interference. I had a similar issue a year ago and tried 5 WIFI routers in just over a month. All had 2.4 GHZ connection issues(Staples got tired of me returning routers). 5 GHZ was OK. Even tried two Asus RT-N66R's one of which Asus told me to take back to Best Buy. I had shut all my PC's down to go on vacation. The router was working fine when I got home until I turned on my desktop PC which was connected to the monitor with HDMI. BAM! 2.4 gone. Shut down the PC and the WIFI came back up. Out with the HDMI cable and video card and the WIFI was back up! Have been using VGA cable for a year with no issues!!! My original WNDR3800 router I thought was dead still works. But I will not trade the RT-N66R running John's fork of Merlin firmware!!!

bb

 

[simon451]

Thanks for the input bbunge. Well, unfortunately still getting the problem. I have been in touch with Asus support so hopefully will get some joy there. I've tried updating to the latest Beta firmware as suggested by Asus but still the same problem exists.

Scouring the internet can't find a single example of someone else having the same problem. From my (albeit rather limited!) knowledge surely it is a software glitch, but then I find it so strange that I cannot find another person having the same issue and that resets and different firmwares do not resolve the issue. Have got back in touch with Asus support and hopefully will make some progress there.

 

[bbunge]

Maybe you should go back to an older firmware. Or look up John's fork and try that. Did you try shutting down all the PC's and devices on your network and connection them one at a time? Don't just suspend them but power down completely. Sounds strange but you might find that, yes, there are two of this that have (or rather had) this problem!

bb

 

[pallec]

Thanks for the input bbunge. Well, unfortunately still getting the problem. I have been in touch with Asus support so hopefully will get some joy there. I've tried updating to the latest Beta firmware as suggested by Asus but still the same problem exists.

Scouring the internet can't find a single example of someone else having the same problem. From my (albeit rather limited!) knowledge surely it is a software glitch, but then I find it so strange that I cannot find another person having the same issue and that resets and different firmwares do not resolve the issue. Have got back in touch with Asus support and hopefully will make some progress there.

I have the exact same problem.!

Approx. a week ago my 2.4GHz started dropping clients and they can't reconnect.

I have not done any changes or firmware upgrades and have no other 2.4GHz networks in my area.

5GHz works fine.

 

[majesty_nl]

Hi All,

i do have the sames issues now. Last week i updated the router because the i saw the firmware upgrade message in the control panel.
Since the update my 2.4Ghz drops every few hours. All connection to that SSID drops and dont connect anymore. I even cant see the SSID anymore.
5Ghz and wired works fine.

- Never had this issue since i have bought this thing (always updated to latest firmware)
- All my connections and setting are same as begin
- Tried different settings in Channels but same issue
- Did upgrade to merlin 2 days ago, still same issue

My last change today: Cleared the NVRAM with telnet. Configured everything manually again. (Checked the CP and its still on Merlin Firmware)
hope this last change will help.

Dont understand whats going wrong, only mad at myself why i did update this thing.
Still 1 Golden rule: Never update a working system.

Will update what my last step did do....

 

[majesty_nl]

So its now +/- 11hrs ago i did do my last change (cleared NVRAM) and still working.
Fingerscross... hopefully tomorrow its still working...

 

[majesty_nl]

Unfortunatly... 2 hrs ago it has dropped the 2Ghz Wireless network again.....
pffffffffff

 

[L&LD]

What, if any, customizations are you doing to the router?

Try the latest 378.55 RMerlin firmware with the following steps:

Unplug all USB devices. Reboot the router and wait 5 minutes.

Flash 378.55 firmware. Reboot the router when asked and then manually reboot the router again (pull the plug and wait for a minute before powering it back on). In the GUI, reset the firmware to factory defaults and reboot the router again (at least twice).

You may want to flash the firmware again at this point (it has helped many with various glitches) and reboot and manually reboot again, followed by another reset to factory defaults via the GUI and a mandatory hard reboot (pull the power plug).

Setup the router manually and minimally to connect to your ISP and secure the router.

'Forget' the old ssid on all clients or better yet, use a new ssid in the router with no spaces or special characters.

Upgrade the wireless drivers on all your devices and make sure to reboot them too at least twice before you test for any further disconnects.

The above should solve your issues.


If not, please give us more details such as the number and types of clients having this issue and any that don't.

 

[majesty_nl]

Thanks for your reply. Have followed exact your steps to be sure your way would help. Cleared also the NVRAM again and again
Will update if this works...

Below answers to your questions:
- Im not doing any special customization, cause first of all i needed to know everything works again.
Did only change the 2.4Ghz to: Only N, Best channel selection (by the way, this was always setup to this)
- Dont have any USB connected

Number of devices:
- Wired (4): Pc Windows 7, XboxOne, Satelite receiver, Samsung TV
- Wireless 2.4Ghz (2): Notebook Windows 7, HTC One
- Wireless 5Ghz (3): Notebook Windows 7, HTC One M8, HTC One M9

So only the Wireless 2.4Ghz devices are disconnecting from the wireless after a while. All other including the Wireless 5Ghz are working fine.
This problem did began when i updated last week to factory firmware update. It has working perfect for 1 year.