Bottom Line: Rescue Mode Does Not Mean Your 8 TB Data Drive Is Lost
The system failed to boot after shutdown, but the user had previously moved app data to the 8 TB drive. The safest recovery order is therefore: try the alternate ZimaOS system slot first, preserve the data disk, and only reinstall the OS if the boot partitions cannot recover.
Try the Alternate ZimaOS Slot Before Reinstalling
Current ZimaOS uses dual system partitions. Connect a monitor and keyboard, open GRUB with the arrow keys, and boot the alternate slot. The ZimaOS system recovery explains the current A/B recovery model.
RAUC's RAUC slot model provides the underlying update model, while the GNU GRUB boot menu covers the bootloader layer.
Do Not Format the 8 TB Data Drive During Recovery
A fresh OS installation and the data disk are separate things. If AppData and media were migrated to the 8 TB drive, protect that disk first. Reinstall ZimaOS only onto the system device.
The ZimaOS installation recovery is the fallback path.
After Reinstall, Reconnect the Existing App Data Deliberately
Do not expect every app to magically rediscover its old configuration. Mount the 8 TB drive, verify the old AppData folders, then reinstall the same applications or point their persistent paths back to the existing data.
The ZimaOS data migration explains current app-data locations and migration behavior.
Why “Ethernet Did Not Load” Was Not a Proven Root Cause
Rescue mode can omit normal networking because the full system never reached its normal services. No Ethernet in rescue therefore does not prove the NIC caused the boot failure. Diagnose boot first; network comes later.
After Recovery, Back Up What Makes Rebuild Expensive
Protect app databases, Compose files, media indexes and irreplaceable user data. A system slot can be restored; recreating years of app state is the costly part.
