Slow downlink for the R650 registered in vSZ

[Hiro]

Hello everyone.

We are always very grateful for your support.

Regarding the issue we've encountered this time, I searched the forum and found another similar topic: https://community.ruckuswireless.com/t5/Access-Points-Indoor-and-Outdoor/Fixes-in-January-2020-r720-...

Similarly, my R650 connected with a Cat6 1Gbps cable has an astonishing uplink speed of 700-900Mbps, but the downlink speed is throttled to around 80-150Mbps as if traffic shaping is in effect. There are no such limitations set by the UTM.

My current environment is as follows:

Controller Version: 6.1.2.0.354

Control Plane Version: 6.1.2.0.187

AP Firmware Version: 6.1.2.0.1003

802.11ax is delivered in dual channels:

2.4GHz: 20MHz -6dB (Background Scan)

5GHz: 80MHz -3dB (ChannelFly)

The following checks have been performed:

The same symptom occurs regardless of the speed of the connected switch port (1Gbps, 2.5Gbps, 5Gbps).

There is no change even when the VLAN is switched to a different route considering the influence of other devices.

The network switch is used as an L2 switch, and no filters or limitations are applied.

Manually fixed power-mode to 802.3at, but no change.

Applied the release note update 6.1.2.0.1003 which mentioned a fix for the tx power issue, but no noticeable change.

Tried enabling/disabling settings like disable-mumimo and ul_mu_mimo, but no improvement.

When a PC is connected to the port to which the problematic R650 was connected, the uplink and downlink speeds are both around 950Mbps.

The switch operates with PoE+ with a utilization rate of below 20%, so there is sufficient margin.

I confirmed the speeds using iperf and fast.com. Strangely, when connecting an H350 and R650 to a switch added to a location with more cascade points than the problem point, speeds of around 700Mbps were observed for both uplink and downlink. Despite the same settings on the upstream UTM.

Could it be an issue of compatibility with the network switch model itself, even though it's from the same manufacturer? If anyone is familiar with a similar situation or the symptoms, please share your solutions.

Currently considering changing the firmware of the controller from version 6.1.2.0.354 to 6.1.2.0.441.

[dk1089]

Hi

I would also suggest to upgrade the controller to 6.1.2.0.441 and also install the latest AP patch version 6.1.2.0.1392.

Once the controller is upgraded and the latest AP patch is uploaded on the controller.

Apply the latest AP patch to the respective AP Zone and test the behavior.

You can also download the latest AP patch using below URL :

https://support.ruckuswireless.com/software/4094-smartzone-ap-patch-lt-gd-ap-patch-wave-2

Regards

Deepak Kumar

Ruckus Networks

[Hiro · Accepted solution]

Everyone, while I appreciate the various solutions you suggested, I have resolved the issue in my environment.
For those experiencing similar phenomena, please refer to the following.
In conclusion, the cause was noise due to alien crosstalk.

The use of high-speed ports with less effective noise countermeasures than higher-end models made it difficult to identify the issue.
Particularly, in some higher-end models, communication was possible from high-speed ports at around 600Mbps despite using Cat6, which complicated identification.

As a fundamental solution, connecting all devices with Cat6A would resolve the issue, but due to cost constraints, as a workaround, limiting the speed of high-speed ports to 1000Mbps allowed for the confirmation of 1Gbps downlink.

Please be mindful of noise countermeasures.

Thank you.