zfs discuss - Nov 2007 - [fuse-discuss] cannot mount ''mypool'': Input/output error

On Thu, 2007-11-15 at 07:22 -0800, Nabeel Saad wrote:
> Hello, 
> 
> I have a question about using ZFS with Fuse.  A little bit of background of
what we''ve been doing first...  We recently had an issue with a Solaris
server where the permissions of the main system files in /etc and such were
changed.  On server restart, Solaris threw an error and it was not possible to
log in, even as root.
> 
> So, given that it''s the only Solaris machine we have, we took out
the drive and after much trouble trying with different machines, we connected it
to Linux 2005 Limited Edition server using a USB to SATA connector.  The linux
machine now sees the device in /dev/sda* and I can confirm this by doing the
following:
> 
> [root]# fdisk sda 
> 
> Command (m for help): p 
> 
> Disk sda (Sun disk label): 16 heads, 149 sectors, 65533 cylinders 
> Units = cylinders of 2384 * 512 bytes 
> 
> Device Flag    Start       End    Blocks   Id  System 
> sda1          1719     11169  11264400    2  SunOS root 
> sda2  u          0      1719   2049048    3  SunOS swap 
> sda3             0     65533  78115336    5  Whole disk 
> sda5         16324     65533  58657128    8  SunOS home 
> sda6         11169     16324   6144760    7  SunOS var 
> 
> Given that Solaris uses ZFS,
Solaris *can* use ZFS. ZFS root isn''t supported by any distro (other
than perhaps Indiana). The filesystem you are trying to mount is
probably UFS.
>  we figured to be able to change the permissions, we''ll need to be
able to mount the device.  So, we found Fuse, downloaded, installed it along
with ZFS.  Everything went as expected until the creation of the pool for some
reason.  We''re interested in either sda1, sda3 or sda5, we''ll
know better once we can mount them...
> 
> So, we do ./run.sh & and then the zpool and zfs commands are available.
My ZFS questions come here, once we run the create command, I get the error
directly:
> 
> [root]# zpool create mypool sda 
If you want to destroy the data on /dev/sda then this is a good start.
IF it were ZFS (which it probably isn''t) you''d want to be
using "zpool
import".
> fuse: mount failed: Invalid argument 
> cannot mount ''mypool'': Input/output error 
> 
> However, if I list the pools, clearly it''s been created: 
> 
> [root]# zpool list 
> NAME                    SIZE    USED   AVAIL    CAP  HEALTH     ALTROOT 
> mypool                 74.5G     88K   74.5G     0%  ONLINE     - 
> 
> It seems the issue is with the mounting, and I can''t understand
why:
> 
> [root]# zfs mount mypool 
> fuse: mount failed: Invalid argument 
> cannot mount ''mypool'': Input/output error 
> 
> [root]# zfs mount 
> 
> I had searched through the source code trying to figure out what argument
was considered invalid and found the following:
> 
>     477     if (res == -1) {
>    478         /*
>    479          * Maybe kernel doesn''t support unprivileged
mounts, in this
>    480          * case try falling back to fusermount
>    481          */
>    482         if (errno == EPERM) {
>    483             res = -2;
>    484         } else {
>    485             int errno_save = errno;
>    486             if (mo->blkdev && errno == ENODEV &&
!fuse_mnt_check_fuseblk())
>    487                 fprintf(stderr, "fuse:
''fuseblk'' support missing\n");
>    488             else
>    489                 fprintf(stderr, "fuse: mount failed:
%s\n",
>    490                         strerror(errno_save));
>    491         }
>    492 
>    493         goto out_close;
>    494     }
> 
> in the following file: 
> 
> http://cvs.opensolaris.org/source/xref/fuse/libfuse/mount.c 
This is the OpenSolaris fuse code, you''re using FUSE on Linux. You
should check with the Linux FUSE community...

-Mark