[gentoo-user] [SOLVED] Balky mounting of external devices

[Walter Dnes]

On Sat, Oct 22, 2011 at 09:21:50PM +0100, Neil Bothwick wrote

> This came up recently with a different subject. Your device does not have
> a partition table, instead the filesystem occupies the whole device
> (sometimes referred to as a "superfloppy" format). There's nothing wrong
> with this, I have a couple of USB sticks like it, and my Nexus S is the
> same.
>
> Your automounter should still pick it up.

  I don't use an automounter.  I like to be in control of what gets
mounted when.  Thanks for the explanation.  With it in mind I've finally
come up with a plan that works.  In /etc/sudoers.d/001 I've included...

waltdnes    i3 = (root) NOPASSWD: /sbin/fdisk -l /dev/sdc

  And there's an entry for a vfat device in /etc/fstab for directory
/mnt/extc.  The command "/sbin/fdisk -l /dev/sdc" seems to read in the
partition table into the system and things work from there on in.  fdisk
only works as root, hence the sudo command.  Here's a sample session...

===================================================================
waltdnes@i3 ~ $ mount /mnt/extc        
mount: special device /dev/sdc1 does not exist
waltdnes@i3 ~ $ sudo /sbin/fdisk -l /dev/sdc

Disk /dev/sdc: 16.0 GB, 16012804096 bytes
256 heads, 63 sectors/track, 1939 cylinders, total 31275008 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1   *        2048    31275007    15636480    c  W95 FAT32 (LBA)
waltdnes@i3 ~ $ mount /mnt/extc
waltdnes@i3 ~ $
===================================================================

  The mount after "sudo /sbin/fdisk -l /dev/sdc" is successful.  So all
I need is a short script "~/bin/mntc" like so...

#!/bin/bash
sudo /sbin/fdisk -l /dev/sdc
mount /mnt/extc

-- 
Walter Dnes <waltdnes@××××××××.org>