strange connectivity issues with router

[lordv]

I am running the latest version (.72) and have been having some issues. The issues actually started cropping up last week while I was still on the previous release (.71?). Just today something happened (not sure what) and I had to power down the router and power it back up to restore connectivity. This is similar to the issues I experienced when I initially purchased one of these routers. Basically the items that are connected via a wired connection are still able to browse the net, but all new connections (wired or wireless) have 0 connectivity. The strange part is that things are able to connect to the network, they just can't get out. Today while I was experiencing this issue I was not able to actually connect to the Asus router to investigate what was going on. What sort of info can I provide to try to figure out what is going on here?

 

[joegreat]

I am running the latest version (.72) and have been having some issues.

Hi,

Which router are you talking about?

The latest Merlin firmware (this section of the forum) is .32. Again: Which firmware are you talking about?
Or you simple posted in the wrong section?

With kind regards
Joe

 

[Jobine]

Same problem with my RT-AC66U with 3.0.0.4.374.32 firmware.

and when I download a file, the connection seems to pause and restart after a few seconds.

 

[lordv]

Hi,

Which router are you talking about?

The latest Merlin firmware (this section of the forum) is .32. Again: Which firmware are you talking about?
Or you simple posted in the wrong section?

With kind regards
Joe

Sorry, should have been more clear (I was mostly doing this from memory). Firmware is 3.0.0.4.374.32. Router is RT-AC66U. Just had it happen again. If I browse to the router gateway page while it is happening I get something along the lines of "settings have just been changed...." I tried to take a screenshot, but I must have hit the wrong keys. I had to power it off and power it back on to get back up and running. I would like to figure out what is going on. This seems strictly router related to me, but I could be wrong.

 

[RMerlin]

If you have a USB disk plugged in, test without that disk to help isolating the source of the problem.

 

[lordv]

If you have a USB disk plugged in, test without that disk to help isolating the source of the problem.

I have no USB disk plugged in. Are there any logs I can gather for you that will help figure out what is going on? The router just reboot itself and came back online earlier.

 

[RMerlin]

I have no USB disk plugged in. Are there any logs I can gather for you that will help figure out what is going on? The router just reboot itself and came back online earlier.

If the router did reboot itself, then there's nothing you'll be able to find through logging. The most common cause of reboots is if you have a USB disk plugged in, and the Media Server fills up the RAM while scanning it for medias - that does not seem to be the case for you.

You will have to go step by step, testing with as few devices as possible, and adding them to the network until you can determine if a specific device is causing it to reboot, or it's something else.

Otherwise, clearing up nvram and reconfiguring everything from scratch is the only other thing you could do. It would take a serial cable attached to the router's internal console port to do any real troubleshooting of random reboots.

 

[lordv]

Here is what just happened right now: all things that had an already established connection were working fine. anything that wanted to establish a new connection (wired or wirelessly) could not. The devices that already had a connection could not access the router gateway page. Does this seem odd to you?

How would I clear the nvram?

You say disconnecting devices and connecting them one by one to try to figure out what is causing the reboots. I have a question about this. Assuming we locate the device that is causing the reboots, what is the solution and what is the problem? Is it something where said device is somehow saturating the connections for the router? Would moving said device off of the router (assuming it's wired) to a dumb switch resolve anything, or no?

 

[RMerlin]

Here is what just happened right now: all things that had an already established connection were working fine. anything that wanted to establish a new connection (wired or wirelessly) could not. The devices that already had a connection could not access the router gateway page. Does this seem odd to you?

How would I clear the nvram?

Press the reset button for about five seconds, release it, then reconfigure your router once it's done rebooting.

You say disconnecting devices and connecting them one by one to try to figure out what is causing the reboots. I have a question about this. Assuming we locate the device that is causing the reboots, what is the solution and what is the problem? Is it something where said device is somehow saturating the connections for the router? Would moving said device off of the router (assuming it's wired) to a dumb switch resolve anything, or no?

If you track down the issue to a specific device, then you can start looking at its Ethernet cable (could be damaged or incorrectly plugged). If it's a small device, look for firmware upgrades for that device.

 

[iAirJordan]

Hi. I made an account to reply to this. I am on latest ofw and get tnis same thing. It only happens with my tablet though. My iphone and other devices don't do it. I think its asus's new source code? This happens multiple times a day and drives me nuts.

 

[lordv]

Press the reset button for about five seconds, release it, then reconfigure your router once it's done rebooting.



If you track down the issue to a specific device, then you can start looking at its Ethernet cable (could be damaged or incorrectly plugged). If it's a small device, look for firmware upgrades for that device.

Highly unlikely that it is a cable as all the cables used were brand new. I can try the NVRAM reset this weekend. In the meantime, please see below.

This is growing exceedingly frustrating. I am having to reboot the router almost daily (just had to do it a few minutes ago.). Are there no logs that the router outputs that would be helpful in tracking down what is going on? Is the logging tab in the router completely useless? Honestly there are only about 6-10 devices attached to this thing in total, 7 of which are wired. This includes the 8 port switch that I have connected to the device. Clearly something is causing it, unplugging things and plugging them back in is not an efficient means of troubleshooting the issue because there is no specified duration of time in which this issue occurs. There MUST be some sort of log that I can analyze, or send you for analysis to figure out just exactly what in the heck is going on. Please help as this is very frustrating.

 

[RMerlin]

There MUST be some sort of log that I can analyze, or send you for analysis to figure out just exactly what in the heck is going on. Please help as this is very frustrating.

If the router crashes, it means it's no longer able to write anything to a log either. Otherwise it would need to be prescient in writing to its log just a fraction of a second before crashing

In Linux, all kernel-level crash info is sent to the console. In the case of an embedded device such as a router, that means it gets sent to the internal serial port - you need to connect a serial cable to that internal port to see the actual crash info.

 

[zoob]

I get similar issues however my setup is:
AC66U Router 3.0.0.4.372.31
AC66U Bridge 3.0.0.4.372.31

I haven't had time to try a new version yet but I will report back if the new one has any change.

Normally when my laptops with Intel Wifi nics stop being able to communicate - existing connected ones work, newly woken up or booted laptops do not, I need to reset my Bridge.

Very rarely do I need to reset the base router.

It almost feels like the bridge is just jamming up all of the connections to the router preventing new connections from getting any of the "wifis". Signal strength is good, just refuses to route any packets from the new Intel wifi connections.

 

[RMerlin]

Asus are aware of some issues with bridge mode. They will switch to a new SDK in the near future which should help with the bridge issues (amongst other things).

 

[lordv]

If the router crashes, it means it's no longer able to write anything to a log either. Otherwise it would need to be prescient in writing to its log just a fraction of a second before crashing

In Linux, all kernel-level crash info is sent to the console. In the case of an embedded device such as a router, that means it gets sent to the internal serial port - you need to connect a serial cable to that internal port to see the actual crash info.

Thanks for the info. A couple of questions for you. Does the crash info that gets sent to the serial get stored for a period of time, or is it a volatile sort of process that gets overwritten after startup? What sort of serial setup do I need to get the info from this router? Would gathering this info be helpful in troubleshooting the issue? What is the purpose of the log in the WebUI if it doesn't provide much, if any, useful info?

I that is a ton of questions. On the bright side I just cleared the NVRAM and re-setup the router. I will see what happens tomorrow. Fingers crossed that that was all it needed.

 

[RMerlin]

Thanks for the info. A couple of questions for you. Does the crash info that gets sent to the serial get stored for a period of time, or is it a volatile sort of process that gets overwritten after startup? What sort of serial setup do I need to get the info from this router? Would gathering this info be helpful in troubleshooting the issue? What is the purpose of the log in the WebUI if it doesn't provide much, if any, useful info?

The serial port is "live" - you must have a computer connected to it, with a serial terminal running (such as Putty/Kitty/XShell) to read the output.

You need to open the case (which will void warranty - not a good idea if you suspect your router of being defective, to be honest).

You need a special serial cable that can handle TTL level signaling, and a computer with either a standard serial port, or an FTDI interface. See the photos I posted in this thread, especially #7 showing the of serial adapter you would need).

Chances are I wouldn't be able to do much with that output however in your particular case.

The System Log in the router shows what is called "syslog" on Linux. This is where all services will log their output. You will see there the DHCP activity, WAN state changes, service restarts, firewall log entries (if enabled), and so on. It doesn't help with the specific case you are facing, but it's very useful for all other type of things.

 

[lordv]

The serial port is "live" - you must have a computer connected to it, with a serial terminal running (such as Putty/Kitty/XShell) to read the output.

You need to open the case (which will void warranty - not a good idea if you suspect your router of being defective, to be honest).

You need a special serial cable that can handle TTL level signaling, and a computer with either a standard serial port, or an FTDI interface. See the photos I posted in this thread, especially #7 showing the of serial adapter you would need).

Chances are I wouldn't be able to do much with that output however in your particular case.

The System Log in the router shows what is called "syslog" on Linux. This is where all services will log their output. You will see there the DHCP activity, WAN state changes, service restarts, firewall log entries (if enabled), and so on. It doesn't help with the specific case you are facing, but it's very useful for all other type of things.

Thanks again for the responses.

As I am somewhat familiar with linux, I am surprised that the logs wouldn't explain what is happening in my scenario, but I believe you as you have way more experience than I.

I was hoping it was going to be a more standard interface so I could find a typical console/serial cable. Ah well .

In a previous post you mentioned something about bridge mode. Mine is not running in bridge mode (by bridge mode I am assuming that this means bridging this router to another wireless router/WAP), but the behavior is the same. Any other troubleshooting advice?

 

[RMerlin]

The only things left to monitor that I can think of at this point:

1) RAM usage. Check from the Tools -> Sysinfo page from time to time to see if free RAM somehow drops down until it eventually exhausts itself. I am not aware of any leftover memory leak, but just in case your scenario is actually one that I haven't heard about yet

2) Check the temperature, anything under 70C is fine

3) Make sure you don't have any other DHCP server running on your network, which might possibly be "hijacking" clients

 

[lordv]

The only things left to monitor that I can think of at this point:

1) RAM usage. Check from the Tools -> Sysinfo page from time to time to see if free RAM somehow drops down until it eventually exhausts itself. I am not aware of any leftover memory leak, but just in case your scenario is actually one that I haven't heard about yet

2) Check the temperature, anything under 70C is fine

3) Make sure you don't have any other DHCP server running on your network, which might possibly be "hijacking" clients

Thanks again.

1) I haven't noticed any.

2) all good

3) I do have a DHCP server running on my server, but the DHCP server on the router has been disabled.

After clearing the NVRAM the issue hasn't cropped up again just yet. I still need to do some more testing. When I really noticed this happening was when I would use my VPN all day and then come home and try to use the net. Trying to change the default gateway (in the router it's easy) on the server has become what appears to be a herculian task. I will update you as soon as I have more info!