* NAS: Had a breaker trip late Wednesday. Thursday morning no NAS. Uh oh. The "heartbeat LED" was on solid, not blinking. Unplugged and replugged. No change. Darn. The data is on a normal 2.5" rotating drive, but the server[*1][*2] boots from a micro-SD card. Oddly(?), the data (Ubuntu 22.04 minimal) on the SD card partitions was/is fine. The Denx U-boot[*3] stuff lives on the initial sectors outside any partition. The hardkernel people chose to employ a tertiary** bootloader called petitboot (<-- not a typo). Apparently U-boot and/or petitboot got corrupted somehow. The HC4 has a serial port that I _could_ have hooked up if this were a forensic investigation. I elected to do a clean install.

Pretty simple really. Hardkernel has an image on their site. Normally I ssh into the HC4 but it has HDMI and a USB port for mouse and keyboard, which are handy during setup.
--- Upgrade Ubuntu (takes _forever_ on SD card)
--- add a couple of users
--- install and configure
----- nfs-kernel-server 
----- vsftpd
----- webfs

And I''m back in business. Of course, nothing is that simple when I'm the one doing it - I made it into a big project. I did locate my setup notes after the fact. Note to self: Setup notes stored on the NAS are not ideal when the NAS is down. Need to update those and copy them to overtracks and/or google drive. But all seems up and running now, so I'm happy. :)

** I refer to the code inside the Amlogic S905 System-on-chip itself as the primary bootloader, U-Boot as secondary, and petitboot as tertiary. Some people ignore the S905 code and refer to U-Boot as primary.