ASUS N66U and AC68U - Dropping WAN only

[UrbanHaggis]

I've been having repeated problems with an ASUS RT-N66U dropping the WAN connection intermittently. When it happens, the LAN is not affected: wired and wireless devices can continue to see and communicate with each other just fine.

It's gotten so bad that I went out and picked up an AC68U, thinking that maybe the N66U was toast (I've had it for about 3 years). Lo and behold, the AC68U is exhibiting the same behaviour.

Specifics:
ISP: Bell Aliant FibreOp 200/30 mbps (D/U)
Router: ASUS RT-N66U / RT-AC68U running asuswrt-Merlin 376.49_5
Note: ISP modem (Actiontec R1000H) was removed, and ASUS was set up in it's place on VLAN 35 for internet. I do not have FibreOp TV.

Over the past few months I've experienced intermittent WAN connection drops, however nothing in the log files ever seemed to indicate what the issue might be.

I upgraded to the 376.49_5 firmware in the past week or so. (Possibly) since that time, I've noticed that every time I tried to use my AppleTV or Roku3 to watch Netflix or iTunes (streaming movies or music), the WAN dropped and the only way to get it back was to reboot the ASUS (sometimes it took 3 or 4 reboots to restore the connection).
At first I figured that maybe my ASUS N66U was dying, and decided to bite the bullet and replace it with an AC68U which I just set up tonight. Everything seemed to be going great and the performance was awesome, but then I went to put on some music to relax (iTunes Match via my AppleTV) and the WAN died again.

For now I've re-instated the Actiontec and DMZ'd to the ASUS, thus negating the need to enable VLANs on the ASUS. I'll need to try to do some testing under this configuration, but for now I've decided to let it be for the night.

This is so repeatable that there must be a bug somewhere causing the problem.

 

[kneo]

I had similar issues a couple of weeks back and had browsed the forums for a solution. The most probable cause was bad cables and/or faulty modem. Change the cable between your modem and router to CAT5e or CAT6.

 

[UrbanHaggis]

That had been one of my thoughts as well. I had purchased new Cat6 cables and tested each one between the ASUS router and the ONT. They don't seem to be the issue though.

The issue seems to have gotten significantly worse since upgrading the firmware on the router. I had been running a build from October until recently when I moved to the Jan 9th release of Merlin's firmware. Since then, the router is pretty much unreliable. Part of the reason I'm thinking it is firmware related is because both he N66U and the AC68U are exhibiting the same behaviour.

Once I get some time I'll try downgrading them to see what happens, or going to the stock ASUS firmware for a comparison.

 

[ca509]

That had been one of my thoughts as well. I had purchased new Cat6 cables and tested each one between the ASUS router and the ONT. They don't seem to be the issue though.

The issue seems to have gotten significantly worse since upgrading the firmware on the router. I had been running a build from October until recently when I moved to the Jan 9th release of Merlin's firmware. Since then, the router is pretty much unreliable. Part of the reason I'm thinking it is firmware related is because both he N66U and the AC68U are exhibiting the same behaviour.

Once I get some time I'll try downgrading them to see what happens, or going to the stock ASUS firmware for a comparison.

For me it was the same. Since upgrading to 3.0.0.4.378.3813 the WAN would not reconnect after the forced disconnect of my ISP and in general the WAN connection would be unstable.

I'm currently back to 3.0.0.4.376.3626 which works fine for over week now. Maybe you too go back to this firmware, so we could see if it is indeed the last stable firmware available.

 

[UrbanHaggis]

I've loaded the 3.0.0.4.376.3626 firmware on the AC68U, reset to factory defaults and reconfigured only required settings. I'll swap it out later today when I no longer require my network connection for work.

I'll let you know what happens.

 

[UrbanHaggis]

Since going back to stock ASUS firmware, reverting back to 3.0.0.4.376.3626, it seems to be working well now.
I'll continue to monitor it though and still have some more rigorous testing to perform.

I'm curious as to what the root cause is though.

 

[L&LD]

Has the latest firmware been flashed and then directly afterwards a reset to factory defaults been performed? Along with a manual setting of the minimum required settings to secure the router and connect to the ISP? With a full reset, I would also suggest a new ssid or forget and re-associate each device on your network, to me, a new ssid is easier.

Has the modem been unplugged for more than 10 minutes and preferably 30 minutes or more to reset the ISP to Home connection? I would power down all networked devices and give that a try bringing up the modem first and waiting 5 minutes and then the router and waiting another 5 minutes, then, each network client too.

Has the ISP connection been tried with the 'Normal' vs. the 'Aggressive' switch in the gui?

 

[UrbanHaggis]

Has the latest firmware been flashed and then directly afterwards a reset to factory defaults been performed?

- Yes. The latest stable release of merlin's firmware was flashed (376.49_5) followed by a factory defaults reset.

Along with a manual setting of the minimum required settings to secure the router and connect to the ISP? With a full reset, I would also suggest a new ssid or forget and re-associate each device on your network, to me, a new ssid is easier.

- The AC68U was a brand new router and set up with minimum configurations. A temporary SSID was set up at first for testing prior to changing it back to my standard SSID (with new password) and reconfiguring each device.

Has the modem been unplugged for more than 10 minutes and preferably 30 minutes or more to reset the ISP to Home connection? I would power down all networked devices and give that a try bringing up the modem first and waiting 5 minutes and then the router and waiting another 5 minutes, then, each network client too.

- As my setup involves completely removing the ISP provided router (Actiontec R1000H), when i swap routers I first release the IP on the installed router, power down the installed router as well as the Alcatel Lucent ONT for 25 minutes (ISP DHCP lease is 20 min). The ONT is then brought back online and allowed to acquire a link prior to the new router being connected and turned on.

Has the ISP connection been tried with the 'Normal' vs. the 'Aggressive' switch in the gui?

- So far it has been on the Aggressive mode which has always worked.

I feel I should reiterate that the same issue was exhibited on two different routers (ASUS N66U and ASUS AC68U) when running the latest Merlin build. I have always run merlin's firmware on the N66U as per the recommendation of a friend, however even in the past I would see intermittent WAN drops where the internal network is communicating fine however I have no internet connection. These were infrequent and recovered on their own quickly. Typically the only impact I would see was my VPN dropping if I was connected in to work.
Since the update to the most recent build, any internet streaming activity (Netflix, iTunes Match, iTunes movie store) on either my Apple TV or Roku3 would kill my internet connection almost immediately. The ASUS would report that the WAN was connected and assigned an IP, however no traffic would pass to/from the internet. If I disabled and re-enabled the WAN port it would report as disconnected and unable to obtain an IP. Occasionally a reboot would fix it, but I suspect the reboot itself was not the fix and rather it was waiting for the ISP DHCP lease to time out.

Note that in order to replace my ISP's router, I need to configure the ASUS to use VLAN 35 for internet traffic.

 

[ca509]

Has the ISP connection been tried with the 'Normal' vs. the 'Aggressive' switch in the gui?

I have the same problems with PPTP dial-up where no "Agressive" mode exists. Still, using any firmware above 3.0.0.4.376.3626 drops the WAN connection, or lets say, it doesn't reconnect.

I changed the modem, flashed the router incl. factory defaults, changed the cable .. so its definitely something with the firmware, since UrbanHaggis has the same problems with newer firmware than 3.0.0.4.376.3626.

 

[L&LD]

Hopefully Asus can release a fix for this soon then.

 

[ca509]

I don't know if Asus is aware of this.. Maybe RMerlin can helpp.

 

[RMerlin]

I don't know if Asus is aware of this.. Maybe RMerlin can helpp.

I can't. Doesn't happen for me, and no idea why it might be happening.

 

[ca509]

I can't. Doesn't happen for me, and no idea why it might be happening.

OK but thank you anyway. Just one question, in your 50 beta2 thread at the beginning someone posted that now the router doesnt recognize any more when the wan cable is pulled and plugged in again, might this be a reason?

 

[KGB7]

Do you still have same issue when using Actiontec R1000H router??

Test it for 2-3 days with Actiontec R1000H as main router. And if you do have issues, then you will need to contact your ISP customer service and have a tech come out.

 

[RMerlin]

OK but thank you anyway. Just one question, in your 50 beta2 thread at the beginning someone posted that now the router doesnt recognize any more when the wan cable is pulled and plugged in again, might this be a reason?

That might only be the case if for some reason your modem was to "disappear" from the router's port, for instance if the modem had rebooted itself due to a crash or to sync issues with the ISP.

 

[UrbanHaggis]

Do you still have same issue when using Actiontec R1000H router??

Test it for 2-3 days with Actiontec R1000H as main router. And if you do have issues, then you will need to contact your ISP customer service and have a tech come out.

No, I do not have any connection drops when I use the ISP provided Actiontec R1000H router. What I do have is horrible wifi and poor connection to my QNAP NAS when I use the Actiontec. Unfortunately the ISP firmware loaded on the R1000H doesn't have a means to set it to act as a bridge to allow me to use a 3rd party router after it, and the DMZ implementation is flaky at best. Not sure if it's worth noting that the Actiontec defaults to a connection type of RFC1483 via DHCP.

That might only be the case if for some reason your modem was to "disappear" from the router's port, for instance if the modem had rebooted itself due to a crash or to sync issues with the ISP.

In my case I have no modem; I'm plugging the ASUS directly into the ONT.

In my scenario I have the ASUS configured to use VLAN 35 for the internet. I believe that ca509 is using PPTP Dial up. Is there anything common between these configs? Do they both use bridge interfaces? Is there anything we can provide to assist with understanding where the issue may lay?

I used to notice a large number of "received packet with own address as source" messages in the ASUS system logs under the Merlin firmware, however since reverting to the stock ASUS firmware I have not come across them yet. I'll be keeping an eye on it though.

 

[DeHann]

Thank you soooo much!

I spent many hours playing with the RT-AC68U router, GX-D1081 v3 switches, network cables, keystone jacks, etc. at my house today.

This morning I had reconnected the Bell FibreOp DVRs and thought they were the source of the WAN issue.

As a last ditch effort I did an Internet search while in bed which brought me here.

I had completely forgot about the firmware upgrade I did a few days ago and was blaming it all on the DVRs. Doh!

 

[jgree32]

Not sure if it's exactly the same but I had similar issues where the Router status page would report the WAN disconnected frequently.

For me I traced it to some issue with the builtin DDNS service. Since disabling that I have not had an issue.

 

[DeHann]

After further investigation, it seems as though the issue was related to a faulty network cable.

Since replacing all network cables which I had previously crimped with factory ones then proper operation was restored.

NOTE: I am in the process of purchasing a network cable tester. This should help me isolate which cable(s) is/are faulty. And, yes, a network cable tester is something I should have purchased some time ago...

 

[Lanageddon]

WAN dropping... DVR twitchy.

I'm having similar problems as well, I've got a RTN56U running off of Bell FibreOp, and every so often it'll drop the WAN, and won't reconnect until I jump into the GUI and reboot, or physically restart the router. I might try reverting back a few versions to see what that does. I've always had problems with the DVR getting twitchy, and I too had to replace the VERY short Cat 5e cable going from my router to a eight port gigabit switch for the IPTV. I'm beginning to think its more of a Bell issue than my router, because this didn't start happening until they started rolling out FibreOp 3.0.