Hi Paul,This might be a problem with qcontrol in stretch, your fan is also probably not controlled. See this blogpost for a proposed fix: https://blog.spblinux.de/2018/09/debian-with-btrfs-on-qnap-11x-21x-kirkwood/
###################Solution (fixes led, buzzer and fan): #qcontrol needs stretch backports: apt-get -t stretch-backports install qcontrol, so add to /etc/apt/sources.list
deb http://ftp.ch.debian.org/debian/ stretch-backports main and /lib/systemd/system/qcontrold.services is broken: replaces lines Requires=dev-input-by\x2dpath-platform\x2dgpio_keys\x2devent.device After=dev-input-by\x2dpath-platform\x2dgpio_keys\x2devent.device withConditionPathExists=/dev/input/by-path/platform-gpio_keys-event (kernel 4.9) or platform-gpio-keys-event (kernel 3.16)
and afterwards run dpkg –configure qcontrol ################# Cheers, Moritz Am 2018-12-06 15:09, schrieb Paul van der Vlis:
Hello, I have a QNAP TS220 here, used for backups. It runs many years 24/7, every time upgraded. Now Debian9. But I had a problem, I could not access it anymore. A hard reboot did not help, a reboot of my switch did help. So I can access it now again using SSH. I am using mdadm, and the raid seems to be OK. My "problem" is that I see a red/green flashing LED. I have not seen that before, so far I know. Can somebody tell me what it means? Or how I can find that? With regards, Paul van der Vlis