Hello everyone,

I upgraded to Unraid 7.3.1 and my server is currently down. I've done a fair amount of troubleshooting and believe I've hit the known ENOFLASH4 bug, but I haven't been able to resolve it. Hoping someone here can help.

SYSTEM DETAILS

- License type: Basic (purchased 2022)

- Key file: Basic.key present on USB at /boot/config/Basic.key (256 bytes, dated Feb 5 2022)

- PHP version: 8.4.21

- Server name: Unraid

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SYMPTOMS

- After upgrading to 7.3.1, the WebGUI returns HTTP 500 after login

- emhttpd crashes immediately on startup with: emhttpd: Error: (/dev/sda2) not known

- All registration fields in var.ini are null (regBuildTime, regTm, regExp, regGUID, regTy, regTo, regDevs, regGen, regCheck, regFILE)

- Array will not start, Docker containers are down, shares are inaccessible

- Data on array drives is intact and untouched

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USB BOOT DRIVE STATE

- Device: /dev/sda (14.9GB USB DISK MODULE)

- Partition layout: GPT

- sda1: 16MB Microsoft reserved

- sda2: 14.9GB FAT32, LABEL="UNRAID", UUID="38D0-4748", PARTUUID="11d1c8bd-fd48-40c5-8651-d6989220ba8e"

- /boot mounts correctly to /dev/sda2

- Basic.key and Trial.key are both present in /boot/config/

- No GUID or UUID file exists in /boot/config/

- flash.cfg contains only share/export settings, no device identifier

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PHP ERRORS (also encountered and patched)

PHP 8.4 shipped with 7.3.1 introduced stricter type coercion, causing fatal errors in several Dynamix plugin files. I patched these and added fixes to /boot/config/go to persist across reboots:

- /usr/local/emhttp/plugins/dynamix/scripts/monitor line 268 - string * int error on mdResyncSize

- /usr/local/emhttp/plugins/dynamix/template.php line 59 - date() receiving string "(null)" instead of int for regBuildTime

- /usr/local/emhttp/plugins/dynamix.my.servers/include/state.php lines 308/310 - string * int error on regTm and regExp

The WebGUI and Registration page now load, but emhttpd still crashes so all reg fields remain null and the array won't start.

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ROOT CAUSE (suspected)

The upgrade repartitioned the USB from the old legacy whole-device FAT superfloppy layout to GPT. emhttpd cannot identify the boot device under the new layout and crashes immediately. This matches the ENOFLASH4 bug described in forum topic #198869.

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WHAT I'VE TRIED

- Multiple reboots

- Manually starting emhttpd - crashes silently every time

- Checked /usr/local/sbin/ for a registration or identify utility - none found

- Verified key files are present and correct size (256 bytes)

- Checked super.dat and all config files for a GUID - none found

- Emailed Unraid support at [email protected] - awaiting response

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Any help or guidance would be greatly appreciated. Happy to provide additional diagnostics or run any commands needed. Thank you!

11 hours ago, Paul Gibbs said:

Error: (/dev/sda2) not known

Fash drive should only have one partition, and if there are more, Unraid should be on the 1st one, 7.3 is more strict with that.

Backup the flash drive, recreate it using the USB tool, then restore the config folder; that should do it.