Slow WebInterface on NWA50AX Pro

merasil

Hi,

I have a problem with my NWA50AX Pro. Whenever I connect to the (standalone) web interface, the connection is quite slow after login. For example, when I click on Configuration -> Wireless -> AP Management, I get the message "loading". Some menu items load relatively quickly, others sometimes take up to 40-50 seconds.

At first I thought this was normal (albeit annoying), but then I discovered that it makes a difference whether I access the interface via LAN or WLAN. If I access the AP with my laptop via my switch via LAN, everything works very quickly, but if I am connected directly to the AP via WLAN, I have these waiting times...

My new NWA55AXE arrived yesterday and I thought it would have the same problem. Surprisingly, this is not the case. It doesnt matter if i am connected directly via WLAN or LAN, the NWA55AXE webinterface is always fast.

After further research, I realized that the speed of the NWA50AX Pro web interface actually depends on whether I am connected directly via WLAN or accessing the interface "externally". If I am connected to the NWA55AXE and access the web interface from the NWA50AX Pro, everything works perfectly.

Could this be a bug in the firmware of the NWA50AX Pro?
The IP of the AP is 172.30.0.21/24 VLAN 1 (NWA50). The LAN/WLAN from which I connect has the IP range 172.16.0.0/16 VLAN 16. The NWA55AXE has the IP 172.30.0.22/24 and everything works smoothly here, even if I am connected directly to it.

P.S. both are in standalone-mode

Zyxel_Nami

Hello @merasil

To assist you better, could you please confirm if the SSID configuration of the NWA55AXE, which your laptop connects with to access NWA50AX Pro's Web GUI, is the same as the SSID configuration of the NWA50AX?

Please let us know the firmware version your NWA50AX Pro is running.

For a more in-depth analysis, we would need the configuration files from both APs. You can download these by following the steps outlined in the FAQ below. Then, please share with us via the Private Message.

https://community.zyxel.com/en/discussion/19272/how-to-download-the-configuration-file-from-a-zyxel-ap

Thank you

merasil

https://community.zyxel.com/en/discussion/comment/60611#Comment_60611

Hi Nami,

the SSIDs are the same, but the config is slightly different. I don't need some networks at the location where the 55AXE is connected.
Both APs have the latest firmware for the corresponding model.
NWA50AX Pro: V6.65(1)
NWA55AXE: V6.29(3)

I have attached the configs, but removed the PSKs and users/passwords.

(BTW why are the psks encrypted on the 50 but not on the 55?)

i had to zip them because of the upload filter of the forum. I can paste the text of the configs inside a comment if you arent allowed to download a zip-file.

configs.zip

Zyxel_Nami

Hello @merasil

Thank you for sending over your configuration file.

We've successfully applied it to our test device and the web GUI access for the NWA50AX Pro is prompt.

To help us better understand the slow performance you're experiencing, please provide a video recording of the issue. Are there any specific pages encountering slow loading?

Additionally, clearing your browser cache or trying a different browser may resolve any potential caching issues that could cause slowness.

merasil

Hello @Zyxel_Nami,

I have made screen captures of my logins and a few clicks on the web interface. You can see quite clearly that when connecting directly to the NWA50AX via wifi, both the dashboard and the AP management page are very slow. Via LAN or the 55AXE, on the other hand, it is very fast. In the video I also show briefly in the station info which my connected device (172.16.2.148) is. I also cleared my browser cache before doing this.

Edit: I also tested this with my iphone and ipad. Same behavior!

Captures.zip

Zyxel_Nami

Hello @merasil

We've replicated the issue you're experiencing with the NWA50AX Pro's web GUI when connected to its non-management VLAN's SSID.

Our team is currently investigating the root cause and will update you as soon as we have more information.

We appreciate your patience as we work to resolve this matter.

merasil

Hi @Zyxel_Nami,

I seem to have found more problems. Maybe these are related to my original problem.
It concerns the NWA50AX Pro again.
I have assigned different VLANs to my SSIDs on the NWA50AX Pro. A Raspberry Pi zero 2 W is connected to the NWA50AX Pro and the SSID that is in VLAN 23 (172.23.0.0/24).

Today I wanted to connect to the Raspberry Pi via SSH form my Laptop (VLAN 16, 172.16.0.0/22), which worked at first, but then I had to deal with repeated disconnections.

I initially thought that this was a software problem on the Pi and took a fresh SD card and reinstalled the OS -> no improvement.
I then thought that the Pi was broken and took an old Pi 3 -> same problem. I then connected via SSH to another server in the same VLAN as the Pi -> everything was fine.
If I then connect from the server to the Pi -> everything is also fine.

I then thought that my laptop had a problem when I remembered that a similar problem already exists. I then connected my laptop to the NWA55AXE and lo and behold the SSH connection to the Pi works without any problems.

I have tested this excessively and can cause the issue repeatedly.

To summarize:
Laptop, Pi -> connected to NWA50AX: does not work
Laptop, Pi -> connected to NWA50AX via another server in the VLAN like Pi: works
Laptop -> connected to NWA55AXE, Pi -> connected to NWA50AX: works

It seems to be a similar problem (inter VLAN communication dropouts).

Additionally, I noticed that I cannot log in to the web interface with my user and password if I access the page with HTTP instead of HTTPs

rvalle

Hi @Zyxel_Nami, @merasil

I am experiencing the exact same issue with my new NWA90AX PRO, which I am deploying to replace older Zyxell AP.

Many of the flows that pass via the AP experience Freezes (at TCP level, packet capture shows, DUPs, retransmissions, etc) including accessing the WEB and SSH interfaces of the AP itself when from not-administrative WLANs.

Accessing devices connected to the AP, from another WLAN also result in the same issues: Raspberry PIs, and other "Things": Cameras, Printers, etc… all freeze when accessing from one WLAN/VLAN to things on other WLAN/VLAN.

I have been making all sort of tests during 2 days, and the issue seems caused by the AP, because accessing the same tcp flows with similar origin VLAN but via Ethernet instead works fine (same routing, same switching). Also connections WLAN→ AP→INTERNET seem to work just fine. Direct connections within the same SSID also work fine including for the offending devices.

But for some reason connections that originate and finalize in the AP, on different WLAN/VLANs, freeze. Including access to SSH/WEB interface of the AP itself.

It is a very obscure networking problem, but it can be reproduced on every single connection. Also ICMP flows on offending connections work just fine, quick response and no packet loss, but TCP streams freeze constantly, and unfreeze after 30-60s.

I have looked at the diagnostic data and some of the interfaces show high error counts of up to 30% of packets.

merasil

Hi @Zyxel_Nami, @rvalle,

thx for your contribution! I also did some more testing and came to the same conclusion. It seems, that also the rate of which tcp packets gets transmitted does affect the error count. If i just connect via ssh and do nothing. I dont get any disconnects. If i open up nano/vi and start scrolling by holding the down button i nearly get instant disconnected… But when i start scrolling slowly line by line it does keep up the connection.

Anyway, your answer does describe the problem very well and i think this should be at least a good hint for the zyxel team to get to the bottom of it.

I hope we will hear from them soon :) at least with a quick workaround^^

Zyxel_Nami

Hello @merasil and @rvalle

We acknowledge the significance of the issue affecting device management on your NWA50AX Pro and NWA90AX Pro. Please allow us some time to thoroughly work on this case. We will keep you informed with any progress or updates.

Thank you for your patience and understanding.

merasil

Hi @Zyxel_Nami,

of course. Please note, however, that it is not only about device management, but also about communication with devices connected to the AP, as rvalle and I have found out.
The problem seems to be basically with inter-VLAN communication when the start point and end point is on the AP (and the devices connected to it). You can find more information in rvalle's and my previous posts. This may help with troubleshooting.