RT-AX88U + RT-AX58U Upload Speed Drops to 50%

[ScottJ]

I'm running 386.4 on both an RT-AX88U and on a RT-AX58U and I'm pulling my hair out trying to figure out what is happening. When first flashed the routers, running the speedtest under the the Adaptive QoS section, it showed my full available upload/download speeds (200/20), but after a 1min or so, all of a sudden the upload speed drops in half (to 10). This was first happening on the RT-AX88U, so I purchased the RT-AX58U to act as a backup so I could re-flash my main router (the RT-AX88U). I did a complete reset and memory clear of the RT-AX58U once flashed and configured it. When I swapped out my RT-AX88U with the RT-AX58U, it did the same upload speed drop after around a minute. I have QoS turned off on both, so there should be no throttling from QoS. I'm wondering if the Gaming/OpenNAT feature is doing something. Again, I have all of those features turned off as I don't use the router for gaming. I did verify speedtest by running it on my PC and got the same 50% upload drop. BTW - This has been happening for a while. I just now decided to look into it. I got the same behavior running on the 386.3_2 firmware. Just for fun, I dropped a 1gb switch between my modem and the WAN port of the RT-AX88U. I was thrilled when I got my full speed back again, but disappointed when after a couple of minutes, I was back down to 50% upload speed.

Any clue as to what is going on? Any help to isolate this behavior is appreciated. I've seen posts with individuals who were having issues with reduced upload speeds with no resolution. I have to guess that what I am seeing is related.

Let me know if I need to provide any logs and/or settings I'm currently using.

-- Scott

 

[L&LD]

Welcome to the forums @ScottJ.

What firmware was installed before flashing to the latest RMerlin 386.4_0 firmware?

Did you perform a full reset to factory defaults and then do a full/proper setup without using a saved backup config file?

Are you 'blindly using settings and features that worked 'once upon a time', just because they worked before?

What specific settings are you changing after fully resetting it? How are you fully resetting the routers?

What device are you using to test with (is it a mobile device, is it plugged in and set to maximum performance)? Are you using a VPN?

Is your ISP having the issues? Have you contacted them and/or turned off all your ISP networking provided equipment for at least 10 minutes (I like to leave it for an hour, if possible, to fully reset the connection between me and the ISP)?

Your issues are not normal. My guess is that the routers are not in a good/known state (if your ISP is working properly).

Looking forward to any more information you can provide.

 

[ScottJ]

The RT-AX58U was brand new, right out of the box. I immediately flashed it with 386.4 and did a 30 second reset and then a WPS "clear" before doing any configuration. The ISP modem/router has been power-cycled many times and if I connect a laptop directly to the ISP (Comcast) modem, I get the proper speeds, so something is happening on the ASUS. The features I have enabled on the router are the Trend AI Network protection (not the parent control) and I have an OpenVPN server and client running. To help in testing, I turned both of those features off and it didn't make any difference. I do have port forwarding on and redirecting traffic to various servers.

Just to be clear, all features/functions of the router are working fine with the exception of the drop in upload speed.

Thanks for the help!

-- Scott

 

[L&LD]

As I suspected, you have quite a few customizations.

And there is no 30 second reset for Asus routers. And, just power cycling the modem is not enough (it needs a certain amount of time 'off', variable by the ISP provider, to reset the connection between you and them).

I would proceed to fully reset the router and slowly enable the options/features you need, testing before and after each step.

 

[ScottJ]

Thanks L&LD

Since I have the luxury of having an extra router with the RT-AX58U, I'll work with it to reproduce the issue as you suggested by re-flashing/resetting and enabling the features one at a time until the problem appears. I'll post my progress along the way.

 

[L&LD]

And one more (important) point to note.

Just because a router is new, right out of the box, that doesn't mean it doesn't need a full reset (even if not using 3rd party firmware on it).

So much easier to do so when there are no customizations on it than after.