Geom tasting exfat slices

[Kevin Oberman]

On Feb 1, 2014 11:10 PM, "Andrey V. Elsukov" <bu7cher at yandex.ru> wrote:
>
> On 01.02.2014 23:45, Kevin Oberman wrote:
> > I have a slice that is formatted (by Windows) as exfat. I can mount it
with
> > the mount.exfat-fuse command and ti seems to work fine using FUSE and
> > fusefs-exfat. But geom does not see it. There is no /dev/geom directory
>
> What do you expect to see in this directory?


Sorry. I meant /dev/exfat. But it does not look like GEOM groks exFAT.

> > created and "gpart show" returns:
> > # gpart show ada0
> > =>        63  1465149105  ada0  MBR  (699G)
> >           63        1985        - free -  (993K)
> >         2048     2457600     1  ntfs  (1.2G)
> >      2459648   958765056     2  ntfs  (457G)
> >    961224704   471040000     3  ebr  (225G)
> >   1432264704    32878592     4  ntfs  (16G)
> >   1465143296        5872        - free -  (2.9M)
> > The exfat slice is "961224704   471040000     3  ebr  (225G)"
> > In more detail, I get:
> > 3. Name: ada0s3
> >    Mediasize: 241172480000 (225G)
> >    Sectorsize: 512
> >    Stripesize: 4096
> >    Stripeoffset: 0
> >    Mode: r0w0e0
> >    rawtype: 15
> >    length: 241172480000
> >    offset: 492147048448
> >    type: ebr
> >    index: 3
> >    end: 1432264703
> >    start: 961224704
> > More oddly, when I mount the FS, I need to mount ada0s5???
> >
> > Any idea what the heck is going on? I'd really like to get it to
automount
> > with gnome-mount, but hald does not even seem to see it at all. I may
need
> > to format it differently. It shows up on Windows as a "Logical"
partition,
> > not "Primary". I don't understand this.
>
> http://en.wikipedia.org/wiki/Master_boot_record
>
> MBR provides an ability to create 4 partitions. Windows calls them
> "Primary partitions". When you want to create more, you need to use EBR.
>
> http://en.wikipedia.org/wiki/Extended_boot_record
>
> EBR uses one entry in MBR, but can provide many "Logical partitions".
> They all are inside this logical partition. Historically FreeBSD has
> naming convention for these partitions - those indexes start from 5.
> As you can see, your MBR used all 4 primary partitions. Those indexes
> are from s1 to s4. One partition contains EBR. Name of logical
> partitions inside of s3 partition starts from s5. You can see all
> partitions using the command `gpart show -p ada0s3`.
Yes, it does, but it thinks the slice is NTFS when it is actually exFAT.
Should geom recognize exFAT?

1. Name: ada0s5
   Mediasize: 241171431424 (225G)
   Sectorsize: 512
   Stripesize: 4096
   Stripeoffset: 0
   Mode: r1w1e0
   rawtype: 7
   length: 241171431424
   offset: 1048576
   type: ntfs
   index: 1
   end: 471039999
   start: 0

Actually, I only have 4 slices. 3 are NTFS and the other is exFAT. I have
deleted the partition on Windows, but I seem to only be able to create an
EBR partition, for some reason. Maybe something is still retaining a
primary partition and maybe gpart can really delete it. I'd rather use GPT,
but my ThinkPad won't boot from a GPT disk that is not EFT.


If I can get t to be a Primary partition, perhaps GEOM will recognize it,
but I'm not confident of that.

Thanks so much for pointing out the obvious that I was missing. I'll play
aroudn with it some more tomorrow and see what I can get it to do.

>
> --
> WBR, Andrey V. Elsukov