Strange Behavior with Firmware 3.0.0.4.376.3861 on RT-N66R

[naninani]

I recently upgrade my router's firmware to 3.0.0.4.376.3861 and I noticed some strange behavior.

So I upgraded the firmware last week because my ISP thought my router wasn't releasing its lease on an IP (had the same IP for 7 months, which isn't normal).

After uploading the firmware file and getting the login prompt, I held the reset button for 5 seconds. After this I reapplied all of my router's settings by hand. This includes changing the username and password to log into the router. After changing all of the settings, I double checked that I could log into the router through the router's IP address.

So here is where things get weird, I logged in again to check what was my public IP and it was the same. So the tech did something on their side. Something like clearing my router, modem and computer's MAC from their routing tables (had to give my router's MAC). After he told me to check, I was able to login to check the public IP and it was the same.

So he gave up and I decided to power off the modem and the router for a week. Today, was the first time I turned on the modem, router and the computer connected to the router since last week. What I had noticed was that my computer's local IP address was different was my manual assignment, which was set last week. So when I tried to access the router (after disconnecting the WAN cable), I couldn't get in with my credentials. I had used the same credentials from last week, which I wrote on note so that I couldn't make mistakes. Even the default admin/admin combo didn't work.

From there I tried every permutation of mixing and matching my custom credentials and the default. Example: newusername/admin, admin/newpassword, newusername/newpassword, admin/admin.

Nothing worked, so I decided to reset the router by holding the reset button for 5 seconds. I reapplied the settings again and confirmed that it works. I can login and my computer is getting the right manual IP.

So does anyone have any insight on how this could have happened? I don't have this router doing anything special other than being a router, so no VPN, no File Sharing or AiCloud. I have the "Enable Web Access from WAN" set to No. I believe I even have UPnP disabled under WAN. There is no one else living with me, so they can't access the router.

As a side note, I have WPS disabled on both frequency and I double checked it in the Web GUI. However, on my phone I used WiFi Analyzer and for my SSID I can see my encryption type as well as WPS. Does that mean WPS is enabled or just that it has the feature? I thought I was going crazy and I saw that the WPS option under Wireless was Off.

 

[Nullity]

The simplest explanation is the most likely; you forgot the password.

Is your house haunted?

 

[naninani]

I just mentioned that I wrote down the password and username.

I had used the same credentials from last week, which I wrote on note so that I couldn't make mistakes.

The WPS issue also has me confused. If anyone uses Wifi Analyzer on Android, if there is a WPS listed under a SSID does that mean it is enabled?

 

[wouterv]

What firmware is in the router now and what was it before?
I suggest to stay with 3.0.0.4.376.3861 for now, that is the latest formal (non beta) release.
The ISP story is strange, I have the same dynamic WAN IP address since ages, only after a few weeks break with the modem and router of it may change. That is normal behaviour. DHCP will not on purpose change the dynamic addresses, only when an assignment gets released from its cache.
Why bother about the same WAN IP address.

Is WPS still set to OFF in the configuration?
OFF means OFF and it shall not be be indicated.

The problems you see seems to be related to a bad flash ROM.
Or a bad configuration download.

Try to re-install the firmware, followed by a NVRAM erase as follows:

1. Install firmware 3.0.0.4.376.3861
2. Enable Telnet.
3. Access the router through Telnet.
4. Execute the following command: mtd-erase -d nvram
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 a firmware backup file).

 

[naninani]

I don't remember what version the firmware was before.

But I followed your instructions. I had to reset the router again to install the firmware.
2. Enabled Telenet
3. Ran the command
4. Power off the router for 10 minutes
5. Logged in with the default credentials
6. Manually configured everything.

However, what had happened was that after I reconfigured my router, I found that only some of the settings stayed.

What I mean is that the settings I configured up until changing the TX Power for the 5GHz were saved. Everything after that such as LAN settings, WAN settings, new credentials for log in didn't save. I know this because after configuring the router, I powered off for 10 minutes and tried to log in. I couldn't so I tried the previous password and it worked. When I double checked the settings I saw that those settings weren't saved.

I got around this by changing some of the settings, then log out. Wait 2 minutes and power off the router for 10 minutes. Rinse and repeat until the last thing was adding a guest network and changing the login credentials.

Any idea why it only saved some of the settings even after I ran that mtd-erase -d nvram? And while only after doing some settings in 1 sitting, then powering off and powering on did the settings stick (or at least I think it did. Won't know until next week)?

 

[wouterv]

The telnet NVRAM erase command seems to work, I suppose after that the router starts with the setup wizzard.
Settings should be saved after you hit Apply (but even I sometimes confuse myself and forget to Apply or forget to hit that + sign to store DHCP or port assignments).
All symptoms you describe from the first post to the last point to the same problem: bad NVRAM (flash ROM).

What is the temperature of the router? It may be snuggly warm, but not HOT.
High temperature brings electronics to weird behaviour.

Maybe you shall start with a bare minimal configuration (e.g. do not change TX power settings, no USB applications, only that to allow Internet access).

 

[naninani]

The telnet NVRAM erase command seems to work, I suppose after that the router starts with the setup wizzard.
Settings should be saved after you hit Apply (but even I sometimes confuse myself and forget to Apply or forget to hit that + sign to store DHCP or port assignments).
All symptoms you describe from the first post to the last point to the same problem: bad NVRAM (flash ROM).

What is the temperature of the router? It may be snuggly warm, but not HOT.
High temperature brings electronics to weird behaviour.

Maybe you shall start with a bare minimal configuration (e.g. do not change TX power settings, no USB applications, only that to allow Internet access).

The router did start with the setup wizard after powering the router back on after the telnet command.

The thing is that I know I hit Apply after changing the settings because I changed the router password and it asked me to log in with the new password. After I did that, I closed the browser, cleared the cache and was able to use the new password. It wasn't until after I turned off the router for about 10 minutes and back on, did I run into the problem of not being able to login with the new password. Instead the password before it worked and part of the settings acted as if it was never changed.

If my router does have bad NVRAM, how do I fix that and would that affect the router's DHCP ability to get a public IP from my ISP? My ISP believes that my router could be the reason for while I have had the same IP for so much months (which they said should never happen).

How do I check the temperature of the router? As far as I know, the router does get warm. But it is in a big opened area, so there is plenty of air circulation.

 

[wouterv]

The temperature check I asked for was simply by hand, feeling the top of the router, it should be below 60 dg C, more around 45 deg C (you must easily be able to keep your hand on it). Merlin firmware can show you the temperature in the user interface.
Power down, startup and finding that settings are missing or have changed really points to a bad NVRAM.
This requires factory repair.

 

[Ormu]

Strangely enough, looks like I'm having similar problems.

My RT-N66U was off for a few days and I turned it on yesterday. Wired network and internet access was working properly. Today, my laptop was unable to connect to the wifi network. I saw both radio leds on even though I had turned the 2.4 GHz radio off earlier.

I tried to log in to the router web interface but it did not accept my password. I'm at least 99.9% sure that it was correct as I had written it down.

I reset the router using the reset button and started reconfiguring it. After setting the administration password it asked me to enter it. However, the new password did not work. Default password "admin" did not work either. Wifi worked OK with the new credentials.

I reset the router again using WPS + power on method. After reconfiguration, everything seems to work normally. We'll see what happens next. I hope that the wifi encryption has not gone off at some point. I was unable to log in so I couldn't know if there were unwanted users in the network.

Luckily there are a few months of warranty left, just in case the router hardware is failing.