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poor LAN performance on 384.13.1 (AC87U)

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yikyi

Occasional Visitor
Hey there

Thank you for opening this thread! I just hard resetted my AC87U, upgraded from 384.13 to 384.13.1 and configured it as a AP. Furthermore, I deactivated both radios (I only need it as a switch). But now the performance is very poor. I ran some speedtests and got results like:

~40 Mbps down, ~110 Mbps up on cable, compared to
~100 Mbps down, ~50 Mbps up on WiFi (from the ISP router!)

The internet connection itself is a symmetric 10 Gbit/s fiber connection.

How can I improve the data rate, to get closer to 1 Gbit/s?

Thank you very much in advance. Have a great day!

#########################################

Turned out that my computer does not support higher speeds than about 600 mbps and the AC87U provided does speeds when it was properly booted up.
 
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For that use IMO you'd be better off selling the AC87U on ebay or similar website and buying a new GE switch.

For the problem itself, you wrote "I deactivated both radios. But now the performance is poor", did you mean that before turning off the radios the performance was good? In that case use the AC87U for wifi, it's probably better and more configurable than an ISP router's wifi anyway.

Otherwise try a different set of cables and avoid port LAN 1 on the AC87U as it's connected to the router's Quantenna 5 Ghz wifi chip. You could also try to downgrade to 384.12 then factory reset in case it's a (Asus) firmware problem with AP mode on this model. You wouldn't necessarily need to run the latest firmware if just using the AC87U as a switch in a home environment with the wifi turned off, in fact you could also try 380.70.

That's assuming it doesn't have a hardware problem, was the internal switch working ok during the AC87U's previous life as a router? I remember your previous thread when you had other problems with this router.
 
For that use IMO you'd be better off selling the AC87U on ebay or similar website and buying a new GE switch.

That might be true, I'll think about it!

For the problem itself, you wrote "I deactivated both radios. But now the performance is poor", did you mean that before turning off the radios the performance was good? In that case use the AC87U for wifi, it's probably better and more configurable than an ISP router's wifi anyway.

Mhh, I honestly didn't try it before turning off the radio. :/

Otherwise try a different set of cables and avoid port LAN 1 on the AC87U as it's connected to the router's Quantenna 5 Ghz wifi chip. You could also try to downgrade to 384.12 then factory reset in case it's a (Asus) firmware problem with AP mode on this model. You wouldn't necessarily need to run the latest firmware if just using the AC87U as a switch in a home environment with the wifi turned off, in fact you could also try 380.70.

That's good to know about port 1. Should I use the WAN port to connect to the ISP router or one of the LAN ports? Does it matter?

That's assuming it doesn't have a hardware problem, was the internal switch working ok during the AC87U's previous life as a router? I remember your previous thread when you had other problems with this router.

Thank you very much for reminding me of this, I already forgot that I had issues before. Maybe it really is a hardware problem. But first I try different ports.

##################################################################

Now I plugged in my computer on port 2 instead of port 1 and reached

down: ~540 Mbps
up: ~900 Mbps

That's much better, but still only half of what should be possible. I might try with a second hand gigabit switch for comparison. But could there be anything I could try on the asus to further improve the performance?
 
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Normally it should be able to reach ~940 Mb/s both ways without problems, though there may be some Asus firmware bug affecting AP mode for this model as it's quite different to other models in that it has a separate chipset made by Quantenna for the 5 Ghz radio so for example it doesn't support AIMesh, so it's worth trying it with older firmware followed by a factory reset.

It shouldn't make a difference which ports you use other than LAN 1, though it won't hurt if you try different ports.

Also worth trying swapping it with a spare switch as now that you're hitting 540/900 the bottleneck may no longer be the AC87U. There isn't much else you could try.

I also have an AC87U but I've never used it in AP mode and can't try as it's my main router and I need it to stay online, anyways in router mode it reaches ~940 Mb/s both ways consistently.

EDIT: your PC could be the problem if it's running an antivirus or security suite, what speed do you get if you connect it directly to the ISP router?
 
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Well, I tried the speedtest directly connected to the ISP-router and got about ~600 Mbps down, so I guess my PC is the actual bottleneck. However, I tried it then again connected to the AC87U and it went back down to ~90 Mbps. So I guess I will have to retire this device and go for a second hand switch. If I ever need a new router I still might go back to asus and merlin, as I really like the active development and possibilities here. :)

Except someone has a good idea what else I could try?! :) Thank you in advance. :)
 
~90 Mbps smells of one of the links not establishing at gigabit speed after you reconnected it, check on the AC87U Tools page that both links state is 1000 Full Duplex. Choose auto speed and duplex on all devices that give you the choice.

Otherwise have you already tried flashing 380.70 then factory resetting? You could also test switching it to router mode (then using ports LAN 2-3-4 only). In router mode running 384.13_1 I can guarantee you that a fully working AC87U has no speed problem. I have a 1000/100 Mb/s FTTH Internet link that my AC87U maxes out consistently. Then if the problem is still there either the router has a hardware issue or you need to look elsewhere (cables, PC, ISP router).

But yeah it wouldn't make sense to keep the AC87U for that use, consuming more power and taking up more space when all you need is a small switch, which are cheap nowadays. In fact in my experience you can get a brand new one online for about the same as a second hand one if the shipping costs are included, especially during sales like black Friday or year end which are coming. Then you can sell the AC87U and pocket the difference, but first make sure the hardware is good by testing it as suggested above.
 
It seems not to be the best idea to have the switch on the same extension lead as the computer - and power them on at the same time. Because this makes it likely that the computer only get a 100 mbps connection instead of 1 gbps.

Furthermore, I tried it now with a Netgear GS105E smart managed switch and got about the same speed of ~500 mbps down. So I have to assume that it is not a faulty AC87U!

So sad, having a 10 gbps internet connection, but a computer using only 1/20th of it. xD

Anyway, thank you very much for your input and assistance!
 
~500 Mb/s is 5x better than you got in the beginning, if you want more upgrade your PC or use a better OS, try it with Linux on a USB drive.
 
I am quite certain now that it was a Windows issue. I switched to Ubuntu 18.04 an downloads are running now with ~860-ish mbps and uploads with above 900 mbps.

I don't know why I had half of this under windows 10. I had all drivers up-to-date (in search for a solution I even usen DriverMAX pro), and tried some settings which are thought to increase download-speed under windows 10 (I just tried a few tutorials/settings I saw recommended online). But nothing cured the issue.

So the culprit wasn't a faulty router or a merlin - add-on incomptability or malconfiguration that caused the main issue. However, a proper configuration really helps. Good luck to every user and a big thank you to every dev!
 
Glad to hear that and yes Linux is a much better OS, I've been using for years and never looked back and before I was using Mac OS X, Windows is just a no go IMO. If you want an even better distro try Manjaro.
 

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