Automounter tutorial

From Linuxintro
Revision as of 08:58, 24 July 2011 by 84.163.125.164 (talk) (dead links--)

autofs, also called automounter or automount, allows you to connect storage media like a USB disk and have it mounted automatically. For example, if you have two USB disks, and you want to have one mounted as usb-120gb and the other as usb-80gb as soon as you plug them in, this is possible with autofs.

QuickStart

This example assumes you want to plug in a USB disk and have it mounted on /misc/usb.

Ubuntu

This article shows you how to configure autofs so that a USB disk that you attach automatically gets mounted to /misc/usb. Install autofs:

sudo apt-get install autofs

Find out your USB disk's UUID:

hwinfo --block
[...]
  Device Files: /dev/sdc1, /dev/disk/by-id/usb-Myson_Century,_Inc._USB_Mass_Stor
age_Device_100-part1, /dev/disk/by-path/pci-0000:00:1d.7-usb-0:3:1.0-scsi-0:0:0:
0-part1, /dev/disk/by-uuid/84ff6790-9b69-4401-9ba2-43d044af1d30, /dev/disk/by-la
bel/DATALUX

Configure autofs

Have a file /etc/auto.master like this:

/misc   /etc/auto.misc --timeout=60 --ghost

This will create all mount points beneath /misc. The mount points will appear even if they are not active ("ghosts").

Create a file /etc/auto.misc like this:

usb       -fstype=auto            UUID="84ff6790-9b69-4401-9ba2-43d044af1d30"

Start autofs

/etc/init.d/autofs start 

Now you can find your USB disk automatically mounted to /misc/usb.

TroubleShooting

  • You can find log entries from automounter NOT in dmesg but in /var/log/messages.
  • If your device is already mounted, automount may not mount it again. This means you will also have to stop other automounters like gnome-volume-manager.

SuSE

This has been tested on SUSE Linux 10.3 but should work on any SUSE Linux version.

  • Find out your USB disk's UUID:
hwinfo --block
[...]
  Device Files: /dev/sdc1, /dev/disk/by-id/usb-Myson_Century,_Inc._USB_Mass_Stor
age_Device_100-part1, /dev/disk/by-path/pci-0000:00:1d.7-usb-0:3:1.0-scsi-0:0:0:
0-part1, /dev/disk/by-uuid/84ff6790-9b69-4401-9ba2-43d044af1d30, /dev/disk/by-la
bel/DATALUX
  • Have a file /etc/auto.master:
/misc   /etc/auto.misc
+auto.master
  • Have a file /etc/auto.misc:
usb             -fstype=auto            :/dev/disk/by-uuid/84ff6790-9b69-4401-9ba2-43d044af1d30
  • Start your automounter:
/etc/init.d/autofs start

Now, as soon as you plug in your USB disk you will find its content under /misc/usb. If you want this setting to be persistent after booting, run the command:

chkconfig autofs on