[FreeNAS 11] USB grub free magic broken

[bal0an]

After upgrading to FreeNAS-11.0-U4 (54848d13b) two weeks ago my FreeNAS system fails to boot after 3 or 4 days. I did the upgrade by installing FreeNAS 11.0 from scratch on a blank USB stick, then import the FreeNAS 9.3 configuration. Upgrading went without issues. My configuration shuts down ( shutdown -p now) shortly after midnight every day and starts up at 15:00 in the afternoon same day (using the BIOS timer wakeup feature). I have been operating the hardware with FreeNAS 9.3 for a few years without issues.
The current stick is a new transcend USB 2.0 8GB booting in BIOS mode. The stick tests fine with h2testw14. I have tried a different transcend USB 3.0 8GB stick in both in USB 2.0 and USB 3.0 ports with the same issue.
When booting the FreeNAS server runs without issues.
When failing the boot stops with free magic is broken message, or enters a grub boot loop (like here https://forums.freenas.org/index.php?threads/grub-loading-reboot-loop.59332).

I can restore my FreeNAS by running a FreeNAS 11 upgrade installation (create new boot environment), and activating the original boot environment as default boot.

These are the syslog entries just before shutdown:

Code:

Nov 28 00:01:00 freenas /usr/sbin/cron[41617]: (root) CMD (/usr/local/bin/python /usr/local/www/freenasUI/tools/autosnap.py > /dev/null 2>&1)
Nov 28 00:01:00 freenas /usr/sbin/cron[41619]: (root) CMD (PATH="/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:/root/bin" shutdown -p now > /dev/null 2> /dev/null)
Nov 28 00:01:00 freenas /usr/sbin/cron[41621]: (root) CMD (/usr/local/bin/python /usr/local/www/freenasUI/tools/alert.py > /dev/null 2>&1)
Nov 28 00:01:00 freenas /usr/sbin/cron[41622]: (root) CMD (adjkerntz -a > /dev/null 2>&1)
Nov 28 00:01:00 freenas shutdown: power-down by root:
Nov 28 00:01:00 freenas shutdown: power-down by root:
Nov 28 00:01:00 freenas zfsd: Disconnecting from devd.
Nov 28 00:01:00 freenas Stopping cron.
Nov 28 00:01:00 freenas Stopping zfsd.
Nov 28 00:01:01 freenas jexec 1 /usr/pbi/plexmediaserver-amd64/control stop
Nov 28 00:01:02 freenas devd: notify_clients: send() failed; dropping unresponsive client

Are there any known issues where FreeNAS 11 corrupts the boot records of the USB stick?
Any ideas how to identify the root cause?

Andreas

 

[dlavigne]

Have you tried a different model of stick?

 

[bal0an]

I've tried a different brand stick. Last 3 days no issues.