來自 1月, 2023 的部落格

Additional information regarding network intermittently became unresponsive in dense Wi-Fi environments
Chris Lai (Deactivated) 張貼於 1月 14, 2023

中文 | English

We have identified this root cause of issue network intermittently became unresponsive in dense Wi-Fi environments as AWDL, issues can manifest in various ways: transmission rate drops, high latency, Wi-Fi connection periodically getting reset, randomly getting disconnected, and unable to rejoin the network.

Apple has addressed the issues with a fix which is available in the latest macOS release (Resolves an issue in which the network intermittently became unresponsive in dense Wi-Fi environments.), fix is also available on iOS / iPadOS, we strongly recommend all users to update their devices to the latest version listed below to avoid connectivity issues, or apply the workaround provided if unable to update system:

  • macOS Ventura 13.1

  • macOS Monterey 12.6.2

  • macOS Big Sur 11.7.2

  • iOS 16.2

  • iOS 15.7.2

  • iPadOS 16.2

  • iPadOS 15.7.2

  • tvOS 16.2

Note: Due to the peer-to-peer nature of the root cause, in dense Wi-Fi environments will require updating all devices in the network for the issue to be resolve. If not all devices are able to update to latest release, please check the workaround below.

Workaround

The following workaround is suggested for affected devices in order to connect and update their system:

  1. Disable Bluetooth

  2. Set AirDrop to "Allow me to be discovered by: No One"

Updating these settings greatly improves wireless connectivity on affected devices.

The following information is for user who’s familiar with Shell Script and aren’t able to update immediately

If you aren't able to update your system for any reason, Klickklack provides an alternative command to disable AWDL:

sudo ifconfig awdl0 down

Note: macOS will periodically ask you to turn AWDL back on. To suppress the notification, you can run a background script by following the instruction.

  1. Open “Terminal”, copy-paste and run the following command

  2. bash <(curl -sL https://www.kkco.com.tw/wp-content/uploads/2023/01/awdl.sh)

  3. Command prompt will come up, type y and press enter

  4. Command prompt will be asking for your admin password, enter password and press enter

  5. Script is now running in the background

Disable AWDL using a Launch Daemon

The script above will stop running if your macOS reboots or goes to sleep.  Using the Launch Daemon the script will run automatically after a reboot or sleep.

  1. Open “Terminal”, copy-paste and run the following command

  2. curl -sL https://www.kkco.com.tw/wp-content/uploads/2023/01/awdl-daemon.sh | bash

  3. Command prompt will be asking for your admin password, enter password and press enter

  4. Script is now running in the background

Remove the scripts and renable awdl0 interface after system update

  1. Open “Terminal”, copy-paste and run the following command

  2. curl -s https://www.kkco.com.tw/wp-content/uploads/2023/01/cleanup-and-reenable-awdl.sh | bash &> /dev/null

  3. Command prompt will be asking for your admin password, enter password and press enter

  4. Script is now removed and AWDL re-enabled

What is AWDL?

AWDL (Apple Wireless Direct Link) is a low latency, high speed Wi-Fi peer-to peer-connection Apple uses for AirDrop, AirPlay, and perhaps elsewhere. It works using its own dedicated network interface, typically “awdl0".

AWDL will continuously try to discover nearby devices, when active it will lock the Wi-Fi radio for small intervals, quickly hopping between the channels of the active WLAN and AWDL networks.

關於高密度無線網路環境間歇性發生連線異常更多資訊
Chris Lai (Deactivated) 張貼於 1月 14, 2023

中文 | English

可立可目前已確認 AWDL 在高密度無線網路環境會間歇性造成連線異常，異常可能以不同的方式呈現：傳輸速率下降、回應時間提高、Wi-Fi 連線間歇性重置、無預警的中斷連線且無法重新加入網路。

Apple 亦有針對此問題釋出修正，在最新版本的 macOS 中有包含此修正（解決網路在高密度 Wi-Fi 環境中會間歇性沒有回應的問題。），iOS、iPadOS 亦有更新，我們建議使用者更新裝置到下列版本以避免遭遇連線異常狀況，或在無法更新系統時參考暫時解決方法：

  • macOS Ventura 13.1

  • macOS Monterey 12.6.2

  • macOS Big Sur 11.7.2

  • iOS 16.2

  • iOS 15.7.2

  • iPadOS 16.2

  • iPadOS 15.7.2

  • tvOS 16.2

提醒：由於問題根本的點對點功能特性，在高密度無線網路環境下會需要的所有裝置皆更新至最新版本。如果無法所有裝置皆更新至最新版本，請參考暫時解決方案來排除。

暫時解決方法

以下暫時解決方法可供受影響的裝置使用，來重新連上網路並且更新系統：

  1. 關閉藍芽

  2. 將 AirDrop 允許對象設定為「沒有人」

套用以上設定應可大幅改善網路體驗。

以下內容僅針對無法立即更新 macOS 且熟悉 Shell Script 的使用者

如果您的電腦必須留在目前系統版本，可立可另外提供手動關閉 AWDL 的指令：

sudo ifconfig awdl0 down

提醒：macOS 會定時詢問是否要重新啟用 AWDL，如果要停止系統提醒請依照步驟。

  1. 開啟終端機，並複製執行以下指令

  2. bash <(curl -sL https://www.kkco.com.tw/wp-content/uploads/2023/01/awdl.sh)

  3. 系統會提示是否要執行指令，輸入 y 並按下 enter

  4. 此時會需要您輸入系統管理員密碼，輸入完密碼按下 enter

  5. 指令會在背景中自動執行

透過 Launch Daemons 在開機／登入時自動執行指令

以上指令會在系統重新啟動或進入睡眠後停止運作。可以透過 Launch Daemons 使其在開機／登入時自動執行。

  1. 開啟終端機，並複製執行以下指令

  2. curl -sL https://www.kkco.com.tw/wp-content/uploads/2023/01/awdl-daemon.sh | bash

  3. 此時會需要您輸入系統管理員密碼，輸入完密碼按下 enter

  4. 指令會在背景中自動執行

在系統更新完畢後清除 Launch Daemons 自動執行指令並重新啟用 AWDL

  1. 開啟終端機，並複製執行以下指令

  2. curl -s https://www.kkco.com.tw/wp-content/uploads/2023/01/cleanup-and-reenable-awdl.sh | bash &> /dev/null

  3. 此時會需要您輸入系統管理員密碼，輸入完密碼按下 enter

  4. 指令已移除且 AWDL 重新啟用

什麼是 AWDL？

AWDL (Apple Wireless Direct Link) 是 Apple 用於 AirDrop、AirPlay 和其他服務的低延遲高速 Wi-Fi 點對點傳輸功能。通常在裝置上使用獨立的網路介面『awdl0』。

AWDL 會持續的在背景中試著偵測鄰近的裝置，並且在使用時會短暫干擾 Wi-Fi 運作，快速的在目前無線網路連線以及 AWDL 頻道之間來回切換。

Network intermittently became unresponsive in dense Wi-Fi environments
Chris Lai (Deactivated) 張貼於 1月 12, 2023

中文 | English

We have an update regarding this issue, please read more here

We are currently investigating an issue in which the network intermittently became unresponsive in dense Wi-Fi environments. We’ve also performed firmware update and factory reset for cross testing. This issue has been occurring on Apple Silicon devices (M1 / M2 chips) in many sites.

Issue was also reported in a ticket from UCLA IT Services to Apple, which identifies the root cause as AWDL peer-to-peer protocol implemented by AirDrop / AirPlay, whenever AWDL is active it will lock the Wi-Fi radio for small intervals, creating latency spikes and in some cases causing disconnect, the ticket also provides a workaround for affected devices:

  1. Disable Bluetooth

  2. Set AirDrop to "Allow me to be discovered by: No One"

Updating these settings greatly improves wireless connectivity on affected devices.

Apple has addressed the issues with a fix which is available in the latest macOS release (Resolves an issue in which the network intermittently became unresponsive in dense Wi-Fi environments.), fix is also available on iOS / iPadOS, we strongly recommend all users to update their devices to the latest version listed below to avoid connectivity issues:

  • macOS Ventura 13.1

  • macOS Monterey 12.6.2

  • macOS Big Sur 11.7.2

  • iOS 16.2

  • iOS 15.7.2

  • iPadOS 16.2

  • iPadOS 15.7.2

  • tvOS 16.2

高密度無線網路環境間歇性發生連線異常
Chris Lai (Deactivated) 張貼於 1月 12, 2023

中文 | English

針對此異常可立可有更新資訊，請參考此篇文章

可立可正在針對在高密度無線網路環境間歇性發生連線異常的狀況積極進行排查。類似狀況我們也有在其他客戶現場觀察到，上週也透過更新韌體以及重置網路設備等措施進行交叉測試。目前觀察到發生異常的裝置皆為 Apple Silicon (M1 / M2) 裝置。

我們同時有在 UCLA IT 服務團隊向 Apple 提出的障礙通報中看到類似異常狀況，在通報中判斷造成問題的根本原因為 AirDrop / AirPlay 使用的 AWDL 點對點傳輸功能，AWDL 會在使用時短暫佔用 Wi-Fi 頻寬，造成網路回應時間大幅提高甚至中斷連線，通報中同時提到針對受影響裝置的暫時解決方式：

  1. 關閉藍芽

  2. 將 AirDrop 允許對象設定為「沒有人」

受影響的使用者可先透過該方法測試是否目前遇到的問題與該問題相同，套用以上設定應可大幅改善網路體驗。

Apple 亦有針對此問題釋出修正，在最新版本的 macOS 中有包含此修正（解決網路在高密度 Wi-Fi 環境中會間歇性沒有回應的問題。），iOS、iPadOS 亦有更新，我們建議使用者更新裝置到下列版本以避免遭遇連線異常狀況：

  • macOS Ventura 13.1

  • macOS Monterey 12.6.2

  • macOS Big Sur 11.7.2

  • iOS 16.2

  • iOS 15.7.2

  • iPadOS 16.2

  • iPadOS 15.7.2

  • tvOS 16.2