Slow Upload/Download using MR56

[Sjkeith77]

We installed MR56 AP's in two new schools and the network speed are extremely slow.  If I swap out a select few AP's with older Meraki models we do not experience the slow speeds.  I've had a case open with Meraki for almost a year now and they cannot figure out the issue.  We've narrowed the issue down to the MR56 specifically as the MR34,42, and 52 perform just fine.  Any suggestions?

[cmr]

@Sjkeith77 please give more information:

Quantify slow

What clients are you using

What band and channel width in use

What firmware version

I am currently connected to an MR56 running 28.5 and it's working okay, getting ~650Mbps on 5GHz channel 108 from a Samsung S9+

[Sjkeith77]

Clients: Surface Pro 4, Samsung Note 10, Iphone 11, HP x360 G1 Chromebook.

Band: 5GHz 

Channel Width: it was 20 then we switched to 40

Firmware: 27.7.1, we have tried a few on the latest Beta firmware as well.

Slow is we are getting around 50-70Mbps download and 0.25Mbps upload speeds.  We have a 2GBps internet connection and we've ran these test in the off hours to ensure no interference from other users.  We have the SSID set to unlimited per client and SSID.

[cmr]

Is the SSID in bridged mode, do you have 802.11r and 802.11w disabled, bonjour also?

[Sjkeith77]

SSID is bridged with 802.11r enabled.  802.11w is disabled and Bonjour is disabled.

[cmr]

I'd try with 802.11r disabled, what Auth is in use?

[Sjkeith77]

I'll try without 802.1R, We are using 802.1X with on site radius server.  We've also tried disabling 802.1AX per Meraki suggestions and neither seemed to resolve it.  We can unplug and MR56 and plug in an MR42 and get easily 10 times the throughput when doing internet speed tests.

[cmr]

What switches are you using and what port speed / power use is negotiated.  The MR56 I just tested with is only connected at 1Gb to an MS220-8p and is using ~10W of AT power over 12m of cabling.

Edit - deleted paragraph about power saving as it is mainly related to Intel chipsets

[BrandonS]

I have a hard time believing it is the MR hardware. It has to be something in the configuration or environment. How easy is it to reproduce (is always like this or intermittent)? What does the channel utilization and RF spectrum look like? Have you taken one home or to another network? I would try that for my own sanity and to help rule out part of the puzzle, at least. 

[Sjkeith77]

It's slow all the time.  We walked across the street and removed an MR42 and installed it in place of an MR56 and the slowness went away.  We have literally limited it down to just the MR56 model.  Both of those schools are also running the exact same GPON network all attached to the same OLT directly with Single mode fiber.

[Sjkeith77]

The WAPS are also all in the same network so same exact SSID config etc.  I've check rf spectrum and didn't see any high utilization at all or interference except for the 2.4 channels which are garbage anyway.

[BrandonS]

It still seems more likely the combination of your switching and the MR then just the MR. It’s maybe not that relevant, but you could sanity check that by taking one home, I guess. 

What about duplex mismatch or some strange incompatibility with your switch port and the NIC used my MR56? 

Maybe try large packet size pings to the MR to reveal packet loss under load? Something like ping —size 1500 1.2.3.4 has revealed similar sounding issues for me in the past. I don’t envy you having had this on your plate for a year.. good luck. 

[Sjkeith77]

We are using Dasan Zhone 2608T ONT's.  Each port is 1GB, AT power.  The backend system is a GPON network.

[sudoshane]

Are there any updates after disabling 802.11r? I'm facing the exact same issues and wondering if you have found a solution or if you continue to have to reboot the APs each time there is a complaint. 

[Sjkeith77]

This issue has been resolved.  Meraki Support identified an issue after multiple packet captures and airpacket captures, and resolved it with a custom firmware.  The fix I am being told will be included in  BETA 28.6.  I was able to have Meraki install the firmware on close to 200 MR56 AP's.  Thanks everyone for suggestions and help in narrowing down the focus for troubleshooting.

[Jai007]

Do you have any details that you can share about what the bug was and how it is fixed?

[Sjkeith77]

Hold please, I am inquiring about the details.

[chadnick18]

Would like more details too. The majority of our AP's, close to 1,300, are MR56's and we've been having issues with slow connectivity since upgrading to 28.5. Rebooting the AP's temporarily resolves the issue. The issue happens with all different clients. When doing speed tests download speeds will be less than 1 Mbps and while upload speeds will be 200+ Mbps.

[Sjkeith77]

Hello,

I am still awaiting support to tell me the root cause. I am being told the fix is in Stable Release candidate 28.6.  I would upgrade the firmware to 28.6 then test speeds.  28.6 was supposed to be a BETA release but Meraki's thorough testing has classified it as Stable RC.

[AzureInnocence]

Updating to 28.7.1 remediated the issues that the MR56 had on 28.5

Similar issue as yours where Wi-Fi download speeds were limited to barely 4Mbps, while upload speeds were exceeding 200Mbps. Client devices were using NIC Intel ax201 version 22.160.0

[ww]

Can you try using a switch between the 2608t and the ap's.  (With poe or use a poe injector. )

i had some issues with mr mgig ports not working well directly on mx, maybe 2608 has similar issues.