FreeNAS

after testing a variety of vendors we found sandisk and samsung USB sticks to be most compatible and fast (mostly used/tested on our older hardware Asus KGPE-D16 and Supermicro X10SLH-F). we have not yet tested with install on SATA disks.

currently it seems to me that the problems are related to non-UEFI boot/install and we also try to move to UEFI with new hardware.

these are the 2 sticks used for non-UEFI boot (which failed somehow after reboot 11.2 on old asus board, and then had the boot problem when disks were attached to SAS controller on SM-X11SCA-F).
if you need more, just ask ;)

[root@samba ~]# camcontrol devlist
<Intenso Speed Line 1.00>          at scbus10 target 0 lun 0 (pass7,da0)
<SanDisk Ultra 1.00>               at scbus12 target 0 lun 0 (pass9,da2)

[root@samba ~]# diskinfo -v da0
da0
        512             # sectorsize
        15977152512     # mediasize in bytes (15G)
        31205376        # mediasize in sectors
        0               # stripesize
        0               # stripeoffset
        1942            # Cylinders according to firmware.
        255             # Heads according to firmware.
        63              # Sectors according to firmware.
        Intenso Speed Line      # Disk descr.
        000000000000000269      # Disk ident.
        No              # TRIM/UNMAP support
        0               # Rotation rate in RPM
        Not_Zoned       # Zone Mode

[root@samba ~]# diskinfo -v da2
da2
        512             # sectorsize
        15376000000     # mediasize in bytes (14G)
        30031250        # mediasize in sectors
        0               # stripesize
        0               # stripeoffset
        1869            # Cylinders according to firmware.
        255             # Heads according to firmware.
        63              # Sectors according to firmware.
        SanDisk Ultra   # Disk descr.
        4C530001181013103554    # Disk ident.
        No              # TRIM/UNMAP support
        Unknown         # Rotation rate in RPM
        Not_Zoned       # Zone Mode

just could get reproduction, see Bug #77062

is 11.2u2 different from FreeNAS-11.3-MASTER-201902231007-e132e27.iso in regards to the boot loader?

is it worth trying again 11.1u6.3 => 11.3 ?

11.2u2 has no changes to the boot loader. 11.3 is what needs to be tested. I am more interested in testing if the issues with the boot loader itself are resolved at this point, but if you want to test the upgrade path be my guest. Do understand that 11.3 is considered experimental and should not be used in production.

i tested a fresh install 11.1u6.3, upgrade into nightlies (FreeNAS-11.3-MASTER-201902240940), the boot worked, where 11.2u2 failed. (Asus KGPE-D16). so bootloader in 11.3 seems somewhat fixed.

i am sorry, but i disagree that Bug #77062 is a duplicate:

while this bug is about a problem in the shipped new bootloader, #77062 is about a fundamental problem how/when the bootloader is applied in the update process. completely separate issues. please reconsider.