RT-AC88U drops internet but not wifi every~5minutes

[dom84]

Hi there,

one year ago I bought an Asus RT-AC88U for my local network and everything works fine until last week.
I removed the router from power during my vacation for two weeks and after that the trouble started.

It is setup in AP mode only for Wifi. So its not connected with the WAN-Port, instead its just an "switch" in my network with internet from another router (from my ISP).

The issue:
Every now and then (sometimes every 5mins, sometimes it works for hours without problems, but mostly in short frequencies) the router loses the connection to the internet.
In this time I also cannot access the web admin of the router anymore and the router doesn't respond to pings. "Asus Device Discovery" finds the router all the time, though.
The Wifi is still up. SSID is visible to all devices and all devices can connect to the Wifi with credentials, but the internet connection is lost.
After a few minutes without doing anything its back to normal and its working again.

So it looks like an issue between the ISP router and the RT-AC88U. Since all other devices (a PC and a NAS) plugged in to the ISP router are working without any problem all the time, I come to conclusion the there is something wrong with the RT-AC88U.

I already reset it to factory settings. The first time with saving and importing my settings, and the second time without this step. No change in the behaviour.
I also already switched it off for several minutes and plugged it back in again. As well: no change.

My log after a restart at 13:29. The diconncect happends multiple times in the displayed timeframe. At least at 13:56 and 14:03
Those two most active devices are my Pixel Phone (C6:myixelhone) and a Chromecast (F4:a:Chrome:cast)



I now out of ideas. Anybody with a hint what happens here?

 

[OzarkEdge]

Hi there,

one year ago I bought an Asus RT-AC88U for my local network and everything works fine until last week.
I removed the router from power during my vacation for two weeks and after that the trouble started.

It is setup in AP mode only for Wifi. So its not connected with the WAN-Port, instead its just an "switch" in my network with internet from another router (from my ISP).

The issue:
Every now and then (sometimes every 5mins, sometimes it works for hours without problems, but mostly in short frequencies) the router loses the connection to the internet.
In this time I also cannot access the web admin of the router anymore and the router doesn't respond to pings. "Asus Device Discovery" finds the router all the time, though.
The Wifi is still up. SSID is visible to all devices and all devices can connect to the Wifi with credentials, but the internet connection is lost.
After a few minutes without doing anything its back to normal and its working again.

So it looks like an issue between the ISP router and the RT-AC88U. Since all other devices (a PC and a NAS) plugged in to the ISP router are working without any problem all the time, I come to conclusion the there is something wrong with the RT-AC88U.

I already reset it to factory settings. The first time with saving and importing my settings, and the second time without this step. No change in the behaviour.
I also already switched it off for several minutes and plugged it back in again. As well: no change.

My log after a restart at 13:29. The diconncect happends multiple times in the displayed timeframe. At least at 13:56 and 14:03
Those two most active devices are my Pixel Phone (C6:myixelhone) and a Chromecast (F4:a:Chrome:cast)



I now out of ideas. Anybody with a hint what happens here?

The AC88U has a history of LAN ports5-8 failing... try connecting its wired backhaul to its WAN port (and check the backhaul cable for any damage).

OE

 

[dom84]

The AC88U has a history of LAN ports4-8 failing... try connecting its wired backhaul to its WAN port (and check the backhaul cable for any damage).

OE

Thanks, good hint.
I checked and I used Port 1 in the last year and tried Port 2 yesterday.
Also I tried now to switch to Port 8, but a few minutes after the switch, the problem occurred again.

 

[OzarkEdge]

Thanks, good hint.
I checked and I used Port 1 in the last year and tried Port 2 yesterday.
Also I tried now to switch to Port 8, but a few minutes after the switch, the problem occurred again.

Try the WAN port (and then a different cable).

OE

 

[L&LD]

Note that the failing ports (that should not be used) are Ports 5-8.

 

[OzarkEdge]

Note that the failing ports (that should not be used) are Ports 5-8.

Thanks, typo corrected.

The OP could also try disconnecting all other LAN connections in case one is unhealthy and affecting the AP switch.

OE

 

[dom84]

Thanks for the help!

Since I only use three ethernet cables right now, I tried first only ports 1, 2 an 3 and, after no change, I tested ports 5, 6 and 7. Just to be sure. Same effect.
After I connected the WAN port to the ISP Router it works for an hour, but then the problems started again.
I also used a different cable without any success.

Will now try to disconnect the other LAN connections.