[RPi3] USB Wifi dongle won't work properly on 12.2

    Recently had to rebuild my Pi3 that had been working fine on 12.02 until the SD card started showing signs of failure.

    I use a TP-Link TL-WN822N wireless USB adapter as the Pi's onboard wifi is useless for video playback in its location. Native wifi is disabled via cmdline.txt

    I didn't spot initially on installing that version 12.2 is now the latest and whilst I can connect to the internet and NAS fine, I am unable to make inbound connections to the Pi under SSH or SMB. The LibreELEC firewall is off, and updating to the latest nightly makes no difference.

    Switching back to the onboard wifi I can connect in again fine. I've also tried a new build with 12.02 and that works fine.

    Has support for this adapter (RTL8192EU) been removed?

    Quote from tp3580

    Has support for this adapter (RTL8192EU) been removed?

    The original RTL8192EU vendor driver was dropped in LE11, but in doing that we switched over to the in-kernel RTL8XXXU driver and that remains enabled in the kernel config so LE12 'should' be the same as LE12.2 (other then the kernel being newer).

    With the onboard WiFi enabled (so you can access) connect the USB WiFi stick and reboot to get a clean boot log, then SSH in and run "journalctl | paste" and share the URL here so we can see if anything interesting is logged (or not).

    The realtek device probes first and iwd sees this as phy0 and the internal Broadcom chip as phy1

    Then I see Jun 26 09:44:20 KODI-Kitchen iwd[382]: NEW_INTERFACE failed: Too many open files in system

    After this point I only see ConnMan mentioning wlan0 which has the MAC address of the Broadcom chip. The "Too many open files in system" failure is unusual and normally indicates an internal bug that results in a process leaking file handles; then at some point the OS hits the 'ulimit' value (in LE, this is 1024).

    The first thing I would do is bump up to an LE13 nightly which has newer everything to see if that magically fixes some underlying issue in drivers or iwd or connman. If that doesn't fix it, then this should raise the 'open files' ulimit:

    Code
    echo "ulimit -n 1000000" > /storage/.config/autostart.sh

    Then reboot and see if that changes anything? (if no, share a log again).

    Between the 12.02 and 12.2 stable version, were a lot of nightly images. If you want and have time, you could test few of them, maybe could find which was the first with that wifi issue. That could help the devs to find the root cause. If you are interested, could take a look here: LE 12.0 Nightly