Bash defeated?

fopetesl · 04-16-2010, 11:32 AM

Quote:

Originally Posted by catkin

When I dabbled with automount and it automounted file systems they were listed by df. Could it be that the automounting is not working? Can you post the content of /etc/auto.master and the /etc/auto.* files listed in it, presumably including (maybe only) /etc/auto.vol?

Oh the USB drive gets mounted alright since I use it quite a lot and it's never failed.
/etc/auto.vol:

Code:

#
# $Id: auto.vol,v 1.2 2003/09/29 08:22:35 raven Exp $
#
# This is an automounter map and it has the following format
# key [ -mount-options-separated-by-comma ] location
# Details may be found in the autofs(5) manpage

FLOPPY		-fstype=vfat,rw,sync,umask=002 		:/dev/fd0
CD_DVD		-fstype=iso9660,rw,nosuid,nodev    	:/dev/cdrom
USBDISKA	-fstype=vfat,rw,gid=100,umask=002	:/dev/sda1
USBDISKB 	-fstype=vfat,rw,gid=100,umask=002	:/dev/sdb1
USBDISKC 	-fstype=vfat,rw,gid=100,umask=002	:/dev/sdc1

# the following entries are samples to pique your imagination
#linux		-ro,soft,intr		ftp.example.org:/pub/linux
#boot		-fstype=ext2		:/dev/hda1
#floppy		-fstype=ext2		:/dev/fd0
#e2floppy	-fstype=ext2		:/dev/fd0
#jaz		-fstype=ext2		:/dev/sdc1
#removable	-fstype=ext2		:/dev/hdd

/etc/auto.net:

Code:

#!/bin/sh

# $Id: auto.net,v 1.5 2003/09/29 08:22:35 raven Exp $

# Look at what a host is exporting to determine what we can mount.
# This is very simple, but it appears to work surprisingly well

key="$1"

# add "nosymlink" here if you want to suppress symlinking local filesystems
# add "nonstrict" to make it OK for some filesystems to not mount
opts="-fstype=nfs,hard,intr,nodev,nosuid,nonstrict,rsize=8192,wsize=8192,async"

# Showmount comes in a number of names and varieties.  "showmount" is
# typically an older version which accepts the '--no-headers' flag
# but ignores it.  "kshowmount" is the newer version installed with knfsd,
# which both accepts and acts on the '--no-headers' flag.
#SHOWMOUNT="kshowmount --no-headers -e $key"
#SHOWMOUNT="showmount -e $key | tail +2"

# Newer distributions get this right
SHOWMOUNT="/sbin/showmount --no-headers -e $key"

$SHOWMOUNT | LC_ALL=C sort +0 | \
	awk -v key="$key" -v opts="$opts" -- '
	BEGIN		{ ORS=""; first=1 }
			{ if (first) { print opts; first=0 }; print " \\\n\t" $1, key ":" $1 }
	END		{ if (!first) print "\n"; else exit 1 }
	'

The others auto.master and auto.misc are pretty much comments.

pielas · 04-16-2010, 11:58 PM

Maybe use output of /proc/mounts would works.

fopetesl · 04-17-2010, 04:43 AM

Quote:

Originally Posted by pielas

Maybe use output of /proc/mounts would works.

/proc/mounts links to /proc/~self/6448:

Code:

rootfs / rootfs rw 0 0
none /dev ramfs rw 0 0
/dev/sda1 / ext3 rw,data=ordered 0 0
/dev/sda1 /dev/.static/dev ext3 rw,data=ordered 0 0
proc /proc proc rw 0 0
sysfs /sys sysfs rw 0 0
usbfs /proc/bus/usb usbfs rw 0 0
devpts /dev/pts devpts rw 0 0
tmpfs /dev/shm tmpfs rw 0 0
automount(pid5988) /vol autofs rw,fd=4,pgrp=5988,timeout=4,minproto=2,maxproto=4,indirect 0 0
/dev/sdb1 /vol/USBDISKB vfat rw,gid=100,fmask=0002,dmask=0002,codepage=cp437,iocharset=iso8859-1 0 0

also exact copy in /etc/mtab

smoker · 04-17-2010, 09:15 AM

Well if auto.vol always maps USBDISKB to /dev/sdb1 you can test for a block device on /dev/sdb1 similar to my original comment

Code:

if [ -b /dev/sdb1 ]

fopetesl · 04-17-2010, 09:41 AM

Code:

#!/bin/bash
if [ -b /dev/sdb1 ]; then
 echo "Found the device"
else
 echo "Not found: block device!"
fi

Code:

~# ./bashtest
Found the device

So that works but this doesn't

Code:

#!/bin/bash
if [ -b /vol/USBDISKB ]; then
 echo "Found the device"
else
 echo "Not found: block device!"
fi

but

Code:

 ~# ls /vol/USBDISKB

still shows files and directories.

So. You are suggesting only to check for /dev/sdx1?

If /dev/sdb1 is a block device, what is /vol/USBDISKB?

smoker · 04-17-2010, 10:16 AM

Essentially a mount point I guess. And a mount point isn't a block device, it's at the filesystem level, which is why ls works.

i.e.

I have a directory called voice on my usbdisk, I can run ls /media/usbdisk/voice fine, but ls /dev/sde1/voice returns "not a directory".

The only problem I can see with your situation is that sdx is usually used for SATA disks( and SCSI), so if you add a SATA disk to the system your mapping may pick up the wrong disk.

catkin · 04-17-2010, 10:32 AM

Helpful observations, smoker

But the OP reported this code not working

Code:

#!/bin/bash
 if [ -d /vol/USBDISKB ]; then
   echo "Found USB drive"
 else
   echo "Not found: USB drive!"
 fi

I just tested some mount points and bash tests for them being directories do work

Code:

c@CW8:~$ [[ -d / ]] && echo true || echo false
true
c@CW8:~$ [[ -d /var ]] && echo true || echo false
true
c@CW8:~$ [[ -d /srv/bacula ]] && echo true || echo false
true

smoker · 04-17-2010, 10:50 AM

I realise it didn't work on his system. But it works fine on mine so there is some other issue that prevents it being seen as a directory in his case. I did suggest trying to test for a sub-directory of /vol/USBDISKB , I don't know whether the OP tried that or not.

I should say that I've concentrated on getting the script to work, rather than figuring out why it doesn't in the original format.

catkin · 04-17-2010, 10:59 AM

Quote:

Originally Posted by smoker

I realise it didn't work on his system. But it works fine on mine so there is some other issue that prevents it being seen as a directory in his case. I did suggest trying to test for a sub-directory of /vol/USBDISKB , I don't know whether the OP tried that or not.

I should say that I've concentrated on getting the script to work, rather than figuring out why it doesn't in the original format.

Understood. It might be worth running stat /vol/USBDISKB and file /vol/USBDISKB. too.

fopetesl · 04-17-2010, 11:49 AM

Quote:

Originally Posted by catkin

Understood. It might be worth running stat /vol/USBDISKB and file /vol/USBDISKB. too.

~# stat /vol/USBDISKB

Code:

  File: `/vol/USBDISKB'
  Size: 12288     	Blocks: 24         IO Block: 4096   directory
Device: 811h/2065d	Inode: 1           Links: 47
Access: (0775/drwxrwxr-x)  Uid: (    0/    root)   Gid: (  100/   users)
Access: 1970-01-01 01:00:00.000000000 +0100
Modify: 1970-01-01 01:00:00.000000000 +0100
Change: 1970-01-01 01:00:00.000000000 +0100

Where did those timestamps come from??

~# file /vol/USBDISK

Code:

/vol/USBDISKB: directory