gptid's in fstab while installing FreeBSD using ISO

Polytropon freebsd at
Fri Oct 4 19:10:46 UTC 2013

On Fri, 4 Oct 2013 20:04:09 +0530, varanasi sainath wrote:
> Hi All,
> How do I get gptid's as default in fstab while installing using FreeBSD iso
> file (Virtual,machine installation) ?
> Is this possible currently?

As far as I know, the installer "bsdinstall" currently does
not have this option included, but it already offers labeling
the partitions as desired, so you could change the content of
/etc/fstab manually to use labels instead of those device names.
You could do this as a post-installation task while leaving
the installer for the command shell and using an editor to
do this.

> if not how do I achieve this?
> I use guided partitioning while installing - If I were to tweak in to the
> source code which files or drivers I should be focusing on?

I haven't looked into the source yet, but I assume you should
concentrate on the component doing the partitioning tasks as
explained here:

> which drivers write the contents of fstab?

The corresponding installer's component itself which
creates the file according to the partitioning layout
at installation time. I assume the required data will
actually be written when the installer performs the
_real_ installation steps (committing to the installation).

> PS: any reason why we use device names in the place of gptid's as default
> in fstab.

Because it's not always wanted or intended. Next to GPT
partitioning with GPT labels, UFS partitioning is possible
(both MBR and dedicated style), which _may_ have cases
where it needs to be applied. Maybe this can happen when
you have a very strange combination of striping, mirroring,
encryption and other things that require metadata here
and there... The different methods have different capabilities
regarding labels (UFS labels, UFSIDs to be mentioned).
You can find out more about them here:

And read about the different methods of partitioning

Even "hardcoded" device names could also be required,
though I can't imagine such a situation at the moment. :-)
It highly depends on the toolset you're using (the bsdinstall
program, gpart, fdisk & disklabel, newfs only).

PS. I've trimmed the CC list to the freebsd-questions@
    list for my reply, hope that's okay.

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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