Re: [PATCH 2/3] mke2fs: print extra information about existing ext2/3/4 file systems

Karel Zak
2014-05-06T07:44:55Z

On Mon, May 05, 2014 at 02:32:53PM -0400, Theodore Ts'o wrote:
> > BTW, the current trend is to use GPT partition types to identify
> > purpose of the partition filesystem (for example extra GUID for
> > /home). It's FS independent solution and it allows use the right
> > filesystems for the right mountpoints. It's very attractive for
> > example for virtual images where you don't have to setup fstab and
> > identify FS, but you still have (for example) /home on the right
> > place.
>
> But a partition only gets one GUUID and one partition type. So are
> you saying that the GUUID partition type would be used to indicate the
> concept of "this is the file system for /home", *instead* of "this is
> an btrfs file system" or "this is an ext4 file system"?

Yes, GPT partition has two UUIDs,

- UUID = an unique partition identifier
- GUID = partition type identifier

I talked about the type (GUID). Note that this concept is just
another point of view how to mount partitions, I don't think it will
be a mainstream solution for standard machines. Now it's supported by
systemd. More details:

http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/

For old good fstab you can use PARTUUID= to identify partitions and
to bypass filesystem specific identifiers. In this case it's unique
partition identifier, no partition type.

Karel

--
Karel Zak <kzak@redhat.com>