Another AX201 drops 5GHz connection, Linux Mint 20.1

[Rimling]

Hi.

Have new Dell Precision 5550 laptop with Linux Mint 20.1 

At 5GHz, Wi-Fi often drops the connection for 5 to 30 seconds, but the iwconfig shows it as connected.

Trying to fix the issue, updated the kernel from 5.4 to 5.10.

Power management off

Explicit country / region setting

Checked that Wi Fi is configured with WPA2, AES

Disable 802.11ax by

sudo modprobe iwlwifi disable_11ax=1

Tried changing NetworkManager to WICD

Install latest firmware, FW59.

None of this helps.

My router - Mikrotik Hap AC. 

As I read in other people's posts, there is no working solution other than buying a WiFi 6 router.

Is any chance to fixing this problem?

In attach info from SSU script.

[David_G_Intel]

Hello Rimling

Thank you for posting on the Intel️® communities. To investigate this request, please share with us the following:

• When the connection drops, does it restore itself automatically? or do you have to change the settings to get it back?
• Do you have the opportunity to use a WiFi 6 router just for testing?
• Did you check that the routers firmware is up to date and configured correctly?
• Do you also get Bluetooth issues?
• Was it always like this or did it start recently?
• Is this issue happening at home, office environment or both?
• Is this the original adapter that came pre-installed in your system or have you changed/installed a new adapter recently?
• Can you test different networks?

Regards, 

David G 

Intel Customer Support Technician 

[Rimling]

• When the connection drops, does it restore itself automatically? or do you have to change the settings to get it back?
  • Yes, restore automatically
• Do you have the opportunity to use a WiFi 6 router just for testing?
  • I will try with WiFi 6 router, but not now
• Did you check that the routers firmware is up to date and configured correctly?
  • Yes, while troubleshooting, also update firmware
• Do you also get Bluetooth issues?
  • Not use mouse, can't say. Trying to disable BT, nothing changed
• Was it always like this or did it start recently?
  • It was from start, in April
• Is this issue happening at home, office environment or both?

At home. In office was just first day with this laptop, can't remember, if any issues with WiFi. And OS was pure Ubuntu 

• Is this the original adapter that came pre-installed in your system or have you changed/installed a new adapter recently?
  • Original
• Can you test different networks?
  • At next week will try in office

I installed a second WiFi5 router a few days ago, because an additional problem was a weak signal in the place where I use the laptop.

After which the situation is almost good.

The monitor script that constantly pings the router shows lost ping for 1-3 seconds. No wifi or kernel related messages in dmesg

Previously, this time was a more serious and visible impact, during the video conference, the connection was often lost, or I could not listen or speak normally.
And Cisco Anyconnect reconnected.

Now I don't see any problems with the conference or Anyconnect. Ping periodically disappears, but usage is not affected.

The connection speed before to be 26 Mbps on average, now 390 Mbps. Perhaps this was the main problem.

Although the previous laptop worked flawlessly in the same conditions.

It is suspected that the Precision 5550 has antenna problems due to design.

I can say that everything is fine now, if you do not take into account that monitoring shows problems with ping

[David_G_Intel]

Thank you for the information provided, we will continue to work on this request. If you test different troubleshooting steps, please let us know.

Regards, 

David G 

Intel Customer Support Technician 

[David_G_Intel]

To continue, please provide the dmesg logs:

• Please type: # dmesg | grep ASSERT​ 
  • If the output is empty, please follow this wiki: https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi/debugging ​to extract dmesg and trace-cmd.
  • If the output has value, please collect from the wiki FW dump too

Once you retrieve the files, please share them with us.

Regards, 

David G 

Intel Customer Support Technician

[Rimling]

Thanks for attention!

The "dmesg | grep ASSERT" return nothing​.

Attached

- # dmesg > dmesg.log

- # sudo trace-cmd record -e iwlwifi -e mac80211 -e cfg80211 -e iwlwifi_msg 

- ping.txt

About ping.txt. It Contains results of my monitor script. Its run in loop

# timeout 0.5 ping 192.168.1.254

and writes to the log result.  The 192.168.1.254 is IP of my router. If result empty, execute and log

# iwconfig

Into ping.txt I pasted two problem period, [2021-06-15 12:59:02, 2021-06-15 12:59:06] and [2021-06-15 13:00:32, 2021-06-15 13:00:34].

In trace.dat captured both periods. 

Additional, I had a video conference during the capture, did not notice any problems with video or sound. Why ping sometimes disappears, I don't understand

PS.

firmware-version: 59.601f3a66.0 QuZ-a0-hr-b0-59.u

[Rimling]

FW dump can't collect, I don't understand, what is X in wiki

echo 1 > /sys/kernel/debug/iwlwifi/0000\:0X\:00.0/iwlmvm/fw_dbg_collectI 

Found, what is X. But cannot enable this. Trying to run under root 

# echo 1 > /sys/kernel/debug/iwlwifi/0000\:00\:14.3/iwlmvm/fw_dbg_collect
bash: /sys/kernel/debug/iwlwifi/0000:00:14.3/iwlmvm/fw_dbg_collect: Operation not permitted
# ls -l /sys/kernel/debug/iwlwifi/0000:00:14.3/iwlmvm/fw_dbg_collect
--w------- 1 root root 0 Jun 16 10:30 /sys/kernel/debug/iwlwifi/0000:00:14.3/iwlmvm/fw_dbg_collect

 Reboot, check 

# dmesg | grep FW_DBG_PRESET

nothing. And directory 

/sys/devices/virtual/devcoredump

does not exists

[David_G_Intel]

Thank you for the information provided, we are working on this request the updates will be posted on the thread.

Regards, 

David G 

Intel Customer Support Technician 

[David_G_Intel]

After further investigating this request, this issue seems related to the router itself. We recommend checking with the router manufacturer to get the best settings for it or any additional configuration needed.

Please keep in mind that this thread will no longer be monitored by Intel. Thank you for your understanding.  

Regards, 

David G 

Intel Customer Support Technician 

[vmsh0]

Hi,

I have the same issue and the same router. Did you find a solution?

[Rimling]

Hi. 

The settings did not help, I solved the problem by putting another Mikrotik closer to the laptop.

[Rimling]

In general, the impression is that the failures are related more to the quality of the signal than to the drivers and settings. Poor signal reception may also be due to the poor location of the WiFi antennas on my Dell Precision 5550 laptop, the case is all-metal. They are located on the edges of the keyboard where the speakers are. If you cover the speakers at the same time with your hands, the signal drops significantly by 10-12dBm. 

[vmsh0]

In my case, SNR is pretty good, and I'm just a few meters from the router. In no case the Wi-Fi gets "spotty" - it either works at full capacity or it doesn't (but it doesn not disconnect! it just stops forwarding packets from the PC to the router, while the opposite seems to keep working until all the TCP connections drop for lack of ACKs).

I made a script that automatically reconnects when the issue happens, as soon as the script detects the issue it triggers the reconnect and the connection comes back at full rate.

I don't think any of this is coherent with a signal problem, so I think we might be having different issues after all