zroot on 14.0-RELEASE quickly becomes unreadable by the boot loader

Hi everyone,

I had previous thread titled: Can't find bootable partition

I also have a forum thread for this, but it's slow going as my account is not yet verified and each post requires approval: https://forums.freebsd.org/threads/14-0-stopped-booting-mysteriously-zfs-mirror.93101/

Here's what I had to do to produce a non-booting system:

Details:

14.0-RELEASE
x86_64
2x 16TB harddrives
ZFS mirror installed with GPT UEFI.
"Automatic" ZFS install.
8GB RAM
Hardware has ECC and passed memtest.
Fully updated with freebsd-update.
Intel S1260 Atom (non-speculative execution processor)

After writing over 1TB of random data to the filesystem and pressing the reset button on the server, (a regular reboot might've been sufficient as well, but not sure) it booted but the boot loader had "zio_read error: 5" errors plastering over top of the menu. It still booted, nonetheless.

After that successful boot, I rebooted and the boot loader failed quickly, dumping me into a UEFI shell.

I've had at least two similar failures like this already. I don't suspect a full 1TB written is required to cause it. BIOS boot, from a previous install, also did not appear to work. I also don't suspcet that patches, or lack of patches, influences the issue.

It's *possible* that somehow hardware is to blame, but while running the server has had no instability or odd behaviors. I've done make kernel and make world without incident. I've rsynced several TB without issue as well.

Whenever this happens, I can zpool import zroot from the installer and zpool shows no errors. And smartctl shows no errors (this is the third pair of drives I've had this happen with). I've yet to have a zpool scrub come back with errors.

Has anyone else had any issues like this? It's very perplexing and concerning.

Thank you!

-Henrich