HELP upgrade 10.3 to 11.2, now it won't boot!

Rick Miller vrwmiller at
Wed Sep 12 01:24:49 UTC 2018

On Tue, Sep 11, 2018 at 8:27 PM William Dudley <wfdudley at> wrote:

> I started the upgrade from 10.3 to 11.2.
> I followed all the instructions and all "looked OK" until I got to
> the reboot.
> Now the system won't boot.
> copied from a photo of the screen:
> Mounting from ufs:/dev/ad01e failed with error 19.
> (something)dev variables:
> (something)ufs.root.mountfrom=ufs:/dev/ad0s1e
> (something)ufs.root.mountfrom.options=rw
> (something)ual root filesystem specification:
> <fstype>:<device> [options]
>       Mount <device> using filesystem <fstype>
>       and with the specified (optional) option list.
> e.g. ufs:/dev/da0s1a
>        zfs:tank
>        cd9660:/dev/cd0 r0
> and obviously, more stuff intended to be helpful printed below that.

Ugh! This error is the bane of my existence! AFAIK, mountroot() error 19
means the root filesystem cannot be found. vfs.root.mountroot, which is
expected to contain the root filesystem, is derived from /etc/fstab unless
explicitly defined in loader(8)*. Theoretically, you can boot to whatever
root filesystem you may have by defining vfs.root.mountfrom at this prompt.

Entering '?' at this prompt outputs a list of geom managed disk devices.
The root filesystem is expected to be on one of these.

It's unclear how the upgrade was attempted (e.g. freebsd-update(8) or
source update). I've observed this error most when PXE booting bootonly
media, never during an OS upgrade.

You may be able to resolve it by booting the system to external media and
mounting the disk with the root filesystem and modifying /etc/fstab.



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