I had Debian Jessie on a QNAP TS-210 device, which is an arm processes (kirkland architecture). It was running fine for many years, but I needed to use something which required up to date libraries, so I decided to update to Debian 9 (Stretch) since Debian 10 was the last supported distro for my architecture (so I figured upgrading to Debian 9 would be "safer").
At some point attempting to upgrade, something got fudged, and now my nas device doesn't boot at all, just a blinking red light of death. None of the recovery documentation is applicable because I replaced the QNAP firmware with whatever was needed to put Debian on the device.
I have no console access to the device, and it does not seem to boot from USB. However, upon booting after pressing the hardware reset button, it does appear to boot into some sort of recovery mode, as I see it obtaining an IPv6 address from the network. Not an IPv4 address at all, but an IPv6 address only.
That seems to indicate that the machine has some life in it and is not bricked, and that I may be able to rescue it. I am going to look into making a custom rescue cd that boots silently without input and runs sshd with a preconfigured password so I can access it....but that isn't so much my issue.
Say I can access the device while it is in some sort of recovery mode, what do I do to fix the device? Is it a problem with firmware? Or is it nothing to do with firmware and I could just replace the kernel on the harddrive?
What can I do to troubleshoot and begin to regain my device?
