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slow upload on 386.2_4 (Asus RT-AC88U)

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eusagc

Occasional Visitor
Hi all,

Would you please help... Just now I updated my AC88U to 386.2_4, coming from 384.19. Old FW is ok, but starting to get flaky-old. My ISP connection is 150/150 (dl/ul), and right now it's become 150/1 (upload dropped). The peculiar thing is that only wired (!) clients are affected, all wireless clients are fine (except for when the wireless device connects to an AP that is wire-connected to this router, in which case the behavior is the same, i.e., upload drops to ~1mbps).

My update went fine. I started from factory reset, and slowly built my config. I was checking speedtest every now and then (since I encountered a similar problem going from 384.19 to 382.1, described here... https://www.snbforums.com/threads/386-1-possible-upload-issue.70356/#post-666597).

This is our main home router and we're all getting tired of this. But I'm leaving 386.2_4 running for now so that I can give more info to troubleshoot (and hopefully fix it). We can all work-from-home/study-from-home by Zoom-ing with our phones for the meantime, instead of using our desktops.

Any ideas on how how to fix this problem I would really appreciate. Thanks so much.
 
My update went fine. I started from factory reset, and slowly built my config. I was checking speedtest every now and then (since I encountered a similar problem going from 384.19 to 382.1, described here... https://www.snbforums.com/threads/386-1-possible-upload-issue.70356/#post-666597).
So at what point in the setup did the speed slow down? In your other post you said it was when you configured the WAN, but surely you must do that first to be able to perform any speed tests.

The 8 LAN ports on the RT-AC88U are supplied by two different switch chips, in two groups of four. It's possible that one of those groups is not working properly. Do your speed test again and check each LAN socket individually.

Can you give more details about your ISP router and the connections to it. It sounds from your other post that the ISP router is only designed to supply one device but you're using a switch to split the connection between the Asus and some other devices.
 
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So at what point in the setup did the speed slow down? In your other post you said it was when you configured the WAN, but surely you must do that first to be able to perform any speed tests.
Hi! Thanks for taking the time. For today, it was after the router was completely configured. The steps roughly were (a) configure WAN, (b) all other local config (dhcp, QoS, router settings), and (c) all amtm addons. I was using ethernet on my laptop throughout, and was randomly doing speedtests. From the start, I disconnected all other lan cables from the router (except for the one I'm using). When all this was done, as soon as I reconnected the cables, there it was, slow upload. Rebooting the router (and eventually disconnecting all APs again) didn't help. Power cycling everything also no luck, same with disabling QoS...

For the old post, I really wasn't done yet and (being first time it happened) didn't really note down specifically when the problem appeared. It might have been when I was setting the static dhcp clients.

The 8 LAN ports on the RT-AC88U are supplied by two different switch chips, in two groups of four. It's possible that one of those groups is not working properly. Do your speed test again and check each LAN socket individually.
Yes, that's correct, I read this somewhere. 1st group is ports 1 to 4, the 2nd is ports 5 to 8. The cable I use with my laptop is on the 2nd group. The behavior is consistent though, regardless of group. On my laptop I get ~1mbps upload, while a desktop connected to a switch on port 1 (1st group) shows similar figures. For an AP connected to port 2, all clients (wired or wireless) all show slow upload. Thus the problem is not there.

Can you give more details about your ISP router and the connections to it. It sounds from your other post that the ISP router is only designed to supply one device but you're using a switch to split the connection between the Asus and some other devices.
That's correct. The ISP modem-router (gateway) is in router mode, where only port 1 is working (ports 2 to 4 are disabled). I connected an 8-port Gbit switch to this, and from this, there are 3 separate lans (one router on 1 of 3 ports), one of which is the AC88U (in router mode). I can't avoid this cascade of routers for the requirements I need, and so I had to sacrifice a lot of things (VPN server, ddns, etc.). One thing is that in 384.19, this problem was nonexistent, that's why I really find it strange. The other lans also have no issue with slow upload.

Thanks a lot for your help. Cheers!
 
When all this was done, as soon as I reconnected the cables, there it was, slow upload. Rebooting the router (and eventually disconnecting all APs again) didn't help.
Just to be clear, you mean you disconnected all your wired devices apart from your laptop not just AP's?

I can't think of anything that would only effect wired devices but not wireless. Do you have any devices (e.g. switches) that use VLANs? Are you using AiMesh?

That's correct. The ISP modem-router (gateway) is in router mode, where only port 1 is working (ports 2 to 4 are disabled). I connected an 8-port Gbit switch to this, and from this, there are 3 separate lans (one router on 1 of 3 ports), one of which is the AC88U (in router mode). I can't avoid this cascade of routers for the requirements I need, and so I had to sacrifice a lot of things (VPN server, ddns, etc.). One thing is that in 384.19, this problem was nonexistent, that's why I really find it strange. The other lans also have no issue with slow upload.
Although it seems unlikely to be related to your problem do you know why the ISP router disables its port 2 to 4 in router mode? This seems to be the opposite of normal behaviour for combi modem/routers where those ports would only be disabled in bridge mode.
 
Just to be clear, you mean you disconnected all your wired devices apart from your laptop not just AP's?
Yes sir, what you said. And of course the WAN connection remained. The only devices directly connected to a lan port on the AC88U is my laptop and a NAS, the rest are either APs or switches. The NAS, APs and switches were all disconnected during the update.

I can't think of anything that would only effect wired devices but not wireless. Do you have any devices (e.g. switches) that use VLANs? Are you using AiMesh?
Yeah, me neither, and that's why I find it really strange. In fact, it was when I was doing speedtest on my (lan-connected) laptop, when I tried speedtest on my phone, and was perplexed that I got normal behavior there. And so I unplugged my laptop and turned on wifi and also got normal results. From there, I checked on my kid's desktops and phones, and it was consistent -- all wired connections had the problem. I was stumped.

No VLANs here. I used to have them (using Tomato (Shibby, Toastman, and recently, FreshTomato) but I realized it was a pita (finally tore it down when I decided to go Asus with the AC68U and this AC88U, which only had the Merlin option (which didn't have VLANs)).

Never used AiMesh here, though that's one of the reasons why I wanted to update to 386.x.

Although it seems unlikely to be related to your problem do you know why the ISP router disables its port 2 to 4 in router mode? This seems to be the opposite of normal behaviour for combi modem/routers where those ports would only be disabled in bridge mode.
I agree, it has nothing to do with that. For the longest time this modem-router had all ports active. Then I found root login from the web and bridged it, using a Linksys on Tomato as router. But from a few years ago in a FW update they pushed, all ports after port 1 got disabled, and I couldn't find any new root password anymore. This gave me horrible unnecessary work and forced workarounds on my very nice setup, and that's when I decided to go with this back-to-back router topology as the final config.

Come to think of it, you're right. It's in bridge mode where you'd want those ports disabled. But this ISP is like most here, they think their customer base are all dumb, and they want the least in-service customer support possible. When I called CS that time, no one knew that the new FW they pushed disabled those ports, and they wouldn't give me the new root password, it's amazing...
 
Here's what I get on my laptop right now (wired, CAT-5)...
1620953656067.png


On wifi, this is what I get...
1620953568932.png
 
Is there any relevant parameter that differs between network interfaces wl, br and eth? Please see attached printout.
 

Attachments

  • ifconfig.txt
    10 KB · Views: 134
Replace the jumper cable between your router and laptop and try again
If that is not it try a different port on the router
 
Is there any relevant parameter that differs between network interfaces wl, br and eth? Please see attached printout.
I don't have your router model or firmware so I can't directly compare it, but it looks fairly normal AFAICT. If you have link aggregation enabled then try disabling it.

If you upload the complete syslog to pastebin.com we could look at that for clues.

P.S. You don't need to mask the MAC addresses. It doesn't provide any kind of security/privacy and just makes debugging more difficult.

Come to think of it, you're right. It's in bridge mode where you'd want those ports disabled. But this ISP is like most here, they think their customer base are all dumb, and they want the least in-service customer support possible. When I called CS that time, no one knew that the new FW they pushed disabled those ports, and they wouldn't give me the new root password, it's amazing...
I would think that doing a factory reset on the ISP router would restore the function its other LAN ports. Just an idea.
 
Replace the jumper cable between your router and laptop and try again
If that is not it try a different port on the router
Hi! Thanks for having a look at this.

Here's with the port change (moved from port 6 to port 2):
1620954473350.png


Here's with a different lan cable (CAT-6):
1620954795147.png


As I mentioned above, all other wired clients get the same problem. And wireless clients connected to an AP that is ethernet-connected to this router also get slow upload.
 
I don't have your router model or firmware so I can't directly compare it, but it looks fairly normal AFAICT. If you have link aggregation enabled then try disabling it.
Yes, that's understandable. I agree, it looks ok. There's no link aggregation here sir.

If you upload the complete syslog to pastebin.com we could look at that for clues.

P.S. You don't need to mask the MAC addresses. It doesn't provide any kind of security/privacy and just makes debugging more difficult.
Copy on the privacy thing and will do that starting now. Here's the syslog (attached here, can't Pastebin, it's >512kB). I got Scribe running, so would you also need wlceventd.log?

I would think that doing a factory reset on the ISP router would restore the function its other LAN ports. Just an idea.
It's possible, as I would think there's been several newer FW updates since that time. But I would keep it like this for now, since there's no telling if/when they will change their minds again.
 
I got Scribe running, so would you also need wlceventd.log?
I don't use Scribe but from I've seen from other posts its logs miss out a lot of important information. So try to post the original complete router log rather than the Scribe logs.
 
Just a thought....ASUS has been playing with the power save options (including ethernet) to try and bring down the temps on the AC86. Maybe some of those are also being applied on the AC88 and affecting the ethernet port performance?

Somebody who's been experimenting with those have any suggestions on what to look for?
 
I don't use Scribe but from I've seen from other posts its logs miss out a lot of important information. So try to post the original complete router log rather than the Scribe logs.
Copy on the Scribe part and got rid of that now. Here's the complete syslog. Thank you.
 
Just a thought....ASUS has been playing with the power save options (including ethernet) to try and bring down the temps on the AC86. Maybe some of those are also being applied on the AC88 and affecting the ethernet port performance?
Hi! Thanks for your input sir. Dunno about this temp regulation thing until now. But fwiw I've got DC fans running 24/7 on the "newer" hw (including this AC88U) since they tend to get really hot.
 
Copy on the Scribe part and got rid of that now. Here's the complete syslog. Thank you.
We're not seeing any log files. I'm guessing the forum is blocking it. Try uploading it to somewhere like pastebin or dropbox and posting a link to it.

P.S. Do another complete reboot so the syslog contains the entire bootup process after Scribe was removed.

P.P.S. Just as an experiment can you try turning off the WiFi radios (Wireless - Professional) for both bands, rebooting, and see if that effects the wired upload speed. The reason being that (as you discovered in your other thread) the WiFi system has significantly changed in the 386 firmware.
 
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Whoa my bad. Didn't see that the logs were blocked here. Anyhow, it's here...
https://pastebin.com/3nAcbiAu

You'll see the 2 reboots in the latter parts of the file. I didn't remove the lines prior to the 1st reboot just in case you need something there.

I turned off the radios as you suggested, and did speedtest after the reboot. Still no honey though...
1620991842747.png


If you'll check, at about early afternoon, there's log entries pointing to flaky errors on the realtek lan ports (the 2nd group of ports), corresponding to intermittent connection loss on my laptop (Windows icon going from normal "PC" icon to "globe"). It lasts for several seconds and comes back by itself. This happened several times. This is the first time something like this happened afaict, but after an hour or so there were no more such incidents. (The speedtest above is done on the 1st group of lan ports btw.)

Thanks much in advance for taking the time to sort out the huge syslog file. Please take your time. Cheers.
 
Well I'm stumped. Maybe someone with more experience of the RT-AC88U can spot something I can't.

As a last ditch effort can you disconnect all Ethernet LAN cables from the router and then directly connect one Ethernet device which isn't your laptop. Power off the router, wait 30 seconds, turn it back on and test again. This is really clutching at straws.

You said that one of the reasons you updated the firmware from 384.19 was that it was "starting to get flaky". Maybe this is simply faulty hardware? I'd view this as an excuse to buy a nice new router. :)
 
Whoa that was quick! Yes sir, I will do as you suggest and update you tomorrow morning.

I remember when I first tried loading an earlier 386.1, I did a "dirty" flash. And so when this slow upload came up, I thought, well, maybe I just need to start clean this time. But after the nuke reset and a 2nd try gave the same result, I thought there must be something unique in my setup here since no one else is complaining about this problem. So I waited, until it was at least 2 versions down. I still think it had to be that, although what is confusing is that the old FW was fine. And so clutching at straws is fine by me coz because I'm curious to know what's causing it.

You said that one of the reasons you updated the firmware from 384.19 was that it was "starting to get flaky". Maybe this is simply faulty hardware? I'd view this as an excuse to buy a nice new router. :)
By flaky I meant the FW had been running for quite a while now, and may have some gunk now after all the updates and restores... What used to be a monthly scheduled reboot (which was sufficient), I now had to schedule weekly. Otherwise, it starts to get slow/sluggish, and when I check the GUI, I see CPU load staying high, usually caused by dnsmasq or some other process. I don't think it's HW though (or at least I hope not!), since it still works fine.

Please don't get me wrong. Merlin is great stuff. It is at least a stable as Tomato (it's based off it, right?) but it's got more features, esp with the entware/amtm addons. It also allows for some powerful "non-standard" configs, such as specifying DNS on a per-client basis, or "selective" routing for OpenVPN clients. Great stuff indeed!

Buying a new router is not an option for now. The AC88U here is just over 2yrs old, I want to give it at least a year more. Also waiting for AX prices to go down, also waiting for MU-MIMO/OFDMA to actually work in the FW of these routers. Tldr: No man, it's just dang expensive for me to buy a new one right now. Cheers! :D
 
As a last ditch effort can you disconnect all Ethernet LAN cables from the router and then directly connect one Ethernet device which isn't your laptop. Power off the router, wait 30 seconds, turn it back on and test again. This is really clutching at straws.
I followed as you suggested. Still looks the same...
1621042730164.png


I'll probably start this all over just one more time and see if I get lucky. If not, then I'll just go back to trusty-old 384.19 but this time I'll do a factory install instead of a restore. That way I have a clean system again which should be enough till we get the final RCA, or a few more updates along the line.

My sincere thanks for the kind assistance and the time you spent to look into this problem. All the best to you sir. Cheers!
 

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