Meraki MR56 AP Speed Issues

[GrantO]

We have recently purchased and installed 2 new Meraki MR56 APs on top of our existing network, and are finding we are having performance issues when clients are connected. We have a 1gbps dedicated fiber connection, and WiFi 6 clients are only getting top speeds of ~280 mbps (Meraki/Ookla speedtest).

Device: Cisco Meraki MR56
Firmware: MR 27.6
Upstream devices: Netgear GS324TP switch, SonicWall TZ500
Client device tested: Lenovo Yoga 9i, Windows 10 Pro, fully updated (Intel Wi-Fi 6 AX201 adapter)

There is currently only one client device connected to the AP for testing. The AP connection to switch is recognized as 1000 Mbit full duplex. It is running in bridge mode. Set to 5Ghz band only, channel width 80MHz, minimum bitrate 12.  Meraki dashboard reports acceptable utilization on current channel (~10%). Signal strength is good (~35dB). I have checked our SonicWall firewall settings and I am able to get ~900mbps when directly connected to it, we are not using VPN or DPI. I am also able to get ~900mbps speed directly connected to the switch. Connecting AP to same switchport with same cable, top speedtests are around 280 mbps. If I'm not mistaken I understand WiFi is half-duplex so I should at least be seeing speeds of closer to ~400-500mbps for our WiFi 6 client, correct? Any advice or tips to optimize our performance would be greatly appreciated. Thank you!

[PhilipDAth]

If it is a Windows 10 machine, set WiFi performance to "Maximum" for power saving.

powercfg /SETDCVALUEINDEX SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0
powercfg /SETACVALUEINDEX SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0

Disable 2.4Ghz.  Increase minimum bitrate to 12Mhz on the SSID.

[PhilipDAth]

ps. If you have manually forced the channel width to 80Mhz you may find the environment can't handle it.  It can actually slow it down if you don't have a lot of clean spectrum.

If you have forced it to 80Mhz, try dropping down to 40Mhz (after trying the other things) and see if that improves things.

[GrantO]

Thank you, I will attempt those suggestions, I did not see any option in power settings for WiFi performance and assume it was removed in a recent release.

As for the channel width, it was selected automatically by the AP. I will attempt to lower it to 40 MHz and see if that helps.

[NolanHerring]

The channel width at 80MHz is fine, if your environment supports it.

Download a free Windows 10 wireless scanner and see what your RF looks like, and pick a channel that is clean. Feel free to upload your results here for advice. I recommend this (best there is really):  https://www.tethabyte.com/download

Create a text file on your computer being used and paste the following:

:loop
netsh WLAN show interfaces
timeout /t 5
goto loop

Then save, then rename the file from .txt to .bat (make sure you can see extensions in your explorer settings).

Then run the .bat file and it will show you information like your RX/TX rates etc. Feel free to upload those here as well.

Then you can reference this chart, and see which MCS rate your landing on: http://mcsindex.com/

[GrantO]

RSSI: -52 dBm
Noise: -95 dBm
SNR: 43 dB
Signal: 87 %
Frequency: 5500 MHz
Band: 5 GHz
Channel: 100
Channel Width: 80 MHz
Country: US
Beacon Period: 102.4 ms
Min MCS Rate: 36 Mbps
Max MCS Rate: 4803.9 Mbps
Basic Rate Set: 12/18/24/36/48/54
Supported Rates: 12 (B), 18, 24 (B), 36, 48, 54
BSS Type: Infrastructure
Type 802.11: ax
WiFi Generation: 6
Amendments: d e h i k v w
Streams: 8
Stations: 1
Channel Utilization: 10 %

Tried playing around with different channels, channel width set to 40, all recommendations followed. Still only pushing ~280 down ~450 up on speedtests

[NolanHerring]

Try moving to UNII-2, that looks clean.

Also, what driver version is your AX201 running?  Try updating to the latest version.

Assuming the iPerf testing your doing is L2 only?

The Intel AX201 is 2x2, so according to your output, your hitting 1201Mbps which is MCS11, which is as high as it can go. With that rate, and no issues, I would imagine you should be able to hit 800-ish? 

[GrantO]

Was running latest Lenovo provided: 22.0.0.6. Recently installed Intel's generic driver: 22.40.0.7. No improvements noticed.

Moved to a clean channel - no improvements noticed.

Here are results of Iperf testing on local network, first is wifi 6 client to wired server. Second is wired client and server:

[NolanHerring]

Welp that is odd for sure. Assuming the power to the AP is ample and its not running in a low power mode?

Can you try upgrading it to 28.1 (beta) and try again, that might help determine if its a firmware issue or not.

Do you have any other AP's available other than this MR56, to test with?

[NolanHerring]

Another thing if you don't mind trying, is use these commands for the iPerf portion. I've seen big speed differences depending on iPerf CLI commands, and these are the ones that I use when I do my testing.

Try with both

SERVER

iperf3 -s -i 1

CLIENT - TCP

iperf3 -c <server ip address> -i 1 -t <seconds> -w 1000k

CLIENT - UDP

iperf3 -c <server ip address> -u -b 1000M -i 1 -t <seconds>

[GrantO]

Running Iperf again with your recommendations, top is TCP test:

I managed to get my hands on another Wifi 6 client (a Samsung Galaxy S20 FE). Speedtest manages to push ~700 mbps dl ~350 up, interestingly enough. This may be an issue with the Intel WiFi 6 AX201. I will attempt to upgrade firmware on the Meraki. Power as shown in Meraki dashboard is: 12.01 W / PoE 802.3at. We have 2 MR56 APs that have both been tested identically, with similar results.

[cmr]

You seem to be getting better speeds now, nearer 500Mbps, though not quite the 700Mbps that the S20 achieved.  I'll test with the MR56 and MR55 that I have

[cmr]

First tests I did were laptop to laptop, an AX200 to an AX201, this achieved about 310Mbps TCP on the MR56 with an SSID set to 5GHz with an 80MHz channel.  The AP's channel was 80%+ utilised while the test was underway.

I plan to test wireless to wired later today.

[cmr]

Tested to a wired 1Gb NIC on a PC and I get up to 631Mb/s TCP but average is more like 500Mb/s from the NIC below:

Killer(R) Wi-Fi 6 AX1650s 160MHz Wireless Network Adapter (201D2W)

Connection to MR56 is good as below:

5GHz utilisation runs at about 66% while the test is underway.

Laptop is running on battery power, or mains, no difference.

[cmr]

An Intel(R) Wi-Fi 6 AX200 160MHz NIC in a different laptop averages about the same with the same wireless utilisation on the same MR56 that is running 28.99 release 3 (supposedly identical to 28.1).

[cmr]

Testing on the first laptop with the MR55 on the connection below gives about 300Mb/s, note it is only using 40MHz of the band:

[GrantO]

I am currently searching for answers from Intel and Lenovo support communities, since there seems to be no more troubleshooting to be done in terms of networking. It is strange that a phone's WiFi6 adapter is outperforming these brand new Lenovo laptops.

[cmr]

@GrantO it would be interesting to see, I am running driver 22.30.0.11 and having upgraded the APs to 28.1, the result is the same ~500Mb/s on the TCP iPerf test.

[spxmeraki2022]

we were experiencing same performance issues. MR56 speed degrades over time but after restarting AP, speed restores to max. raised case with Meraki/advised to upgrade to 29.3 BETA.

initial tests show firmware stable and WiFi speed improved but any idea when 29.3 STABLE release will be out ?

[cmr]

@spxmeraki2022 it is unlikely that 29.3 will become stable, it is more likely thst 29.4 or similar will be a release candidate and then possibly become stable.