Drive Mount Applet

Table of Contents
Drive Mount Applet

Drive Mount Applet

Drive Mount Applet, shown in Figure 1, allows you to quickly and easily mount and unmount various types of drives and filesystems on your computer. To add this applet to a Panel, right-click on the Panel and choose Panel->Add to panel->Applet->Utility->Drive Mount.

Figure 1. Drive Mount Applet

Background Information for Beginners

	Background Information for Beginners
	Many file systems on Linux and Unix systems must be manually mounted and unmounted. After a file system is mounted, you can read and write to it. When you are finished with a file system, you should unmount it. It is important to unmount removable drives, such as floppy disks and Zip disks, before removing the media, because Linux and Unix systems do not always write the changes made immediately. They typically buffer the changes made to the disk in order to improve the speed of the system. Partitions on fixed drives, such as your hard drive, are typically mounted automatically when your computer boots and unmounted when it shuts down. Removable media must be mounted and unmounted by hand, such as by using the `Drive Mount` applet. The "root filesystem" is the main filesystem on your computer starting with "/" (root). Other filesystems are associated with directories inside the root filesystem. These are called "mount points", which are just empty directories. When a filesystem is mounted, its contents appear inside this directory. As an example, most systems create a mount point "/mnt/floppy" which is just an empty directory if your floppy drive is not mounted. It contains the contents of your floppy if the floppy drive is mounted.

Many file systems on Linux and Unix systems must be manually mounted and unmounted. After a file system is mounted, you can read and write to it. When you are finished with a file system, you should unmount it. It is important to unmount removable drives, such as floppy disks and Zip disks, before removing the media, because Linux and Unix systems do not always write the changes made immediately. They typically buffer the changes made to the disk in order to improve the speed of the system. Partitions on fixed drives, such as your hard drive, are typically mounted automatically when your computer boots and unmounted when it shuts down. Removable media must be mounted and unmounted by hand, such as by using the Drive Mount applet.

The "root filesystem" is the main filesystem on your computer starting with "/" (root). Other filesystems are associated with directories inside the root filesystem. These are called "mount points", which are just empty directories. When a filesystem is mounted, its contents appear inside this directory. As an example, most systems create a mount point "/mnt/floppy" which is just an empty directory if your floppy drive is not mounted. It contains the contents of your floppy if the floppy drive is mounted.

Usage

To mount or unmount a drive, simply click on the Drive Mount Applet icon with the left mouse button. For drives which can eject their media, such as most CDROM's and JAZ drives, you can eject the drive by clicking on the icon with the right mouse button and selecting Eject. To browse the contents of the drive with the GNOME File Manager, select Browse….

Right-clicking on the applet brings up a menu containing the following items:

Browse… — shows the contents of the drive using the GNOME File Manager. The drive must be mounted for this to work.
Eject — ejects the storage medium for drives which can be ejected, such as CDROM's and JAZ drives.
Properties… — opens the Properties dialog.
Help — displays this document.
About… — shows basic information about Drive Mount Applet, including the applet's version and the author's name.

The mount point and mount status of a drive is shown in a tooltip if the cursor is left over the applet for a short time, as shown in Figure 2.

Figure 2. Drive Mount Applet showing tooltip

Customization

You can customize Drive Mount applet by right-clicking on it and choosing Properties…. This will open the Properties dialog(shown in Figure 3), which allows you to change various settings.

Figure 3. Properties dialog

The properties are:

Mount Point — This is the mount point used when mounting the drive. This is an empty directory which will hold the contents of the drive whenever the drive is mounted. Mount points can occur anywhere in your filesystem, but the convention is to put all mount points for removable drives in the /mnt directory.
Update in seconds — This is the interval in seconds at which Drive Mount refreshes its icon by checking the mount status. This is only important if you sometimes mount or unmount a drive using a command or application other than Drive Mount.
Icon — This determines the icons (one for unmounted and one for mounted) displayed for the drive. There are icon sets for most of the commonly used drives (floppy, CDROM, Zip, hard disk, and JAZ). They are shown in Figure 4. You may also select Custom; this allows you to specify your own icons.
Figure 4. Icons for Mounted and Unmounted Drives of Various Types
Notice that Figure 4 shows the icons for the unmounted and mounted states of (from left to right) floppy, CDROM, Zip, JAZ, and hard disk drives.
Custom icon for mounted — A custom icon which is displayed when the drive is mounted. This option is only available if the Icon: selection is set to "Custom".
Custom icon for not mounted — A custom icon which is displayed when the drive is not mounted. This option is only available if the Icon: selection is set to "Custom".
Scale size to panel — Selecting this option scales the size of the mounted and unmounted icons with the Panel's size. If this option is not set, the icon sizes are fixed, independent of the size of the Panel. Selecting this option typically makes for a nicer appearance. For very small Panel sizes, unselecting this option may be useful, as it forces the applet to appear rotated and larger, which makes it easier to see.

Use automount friendly status test — Select this option if you use automount, otherwise leave it unselected.

	Information for Advanced Users
	The default command used by `Drive Mount`to test whether a drive is mounted is stat and would cause the drive to actually be mounted if the user is using `automount`. If this button is selected, it uses mount instead, which does not cause `automount` to mount the drive. The reason this button is not selected by default is that mount is more cpu intensive than stat.

After you have made all the changes you want, click on OK to apply the changes and close the Properties dialog. Click Apply to apply changes without closing. Close closes Properties without saving changes which have not been applied. Applied changes cannot be cancelled.

Configuring Your System

	For Advanced Users
	This section is intended for system administrators and advanced users.

In order for Drive Mount Applet to work properly, the system may need to be configured by the system administrator, using root privileges. This section provides a very basic introduction.

Information describing the mount point and filesystem type of each drive is kept in /etc/fstab. This can be configured by hand or by using the linuxconf application. For drives which do not always have a single filesystem type (such as a floppy drive which may have msdos or ext2 filesystems), you should use "auto" for the filesystem type. Each device has a single line in /etc/fstab of the following form:

    /dev/fd0        /mnt/floppy      auto    noauto,rw,user  0 0

This entry describes the first floppy device (/dev/fd0) as having a mount point of /mnt/floppy, a variable filesystem type which should be automatically detected, and the following configurations: "noauto"— Do not automatically mount the drive when the computer is booted, "rw"— The drive is readable and writable, and "user"— Users have permission to mount the drive. These, along with the last two fields which we do not describe here, are discussed in detail in the fstab man pages, available by typing man fstab or through the GNOME Help Browser.

The linuxconf application provides a graphical interface for controlling these filesystems. To start linuxconf, just type linuxconf in a shell window (you must log in as root). Select Config->filesystems->Access local drive. To edit an entry, just select it. linuxconf is meant to be easy to use and has its own internal help system to guide you through the process. You may also add new entries by selecting the Add button.

Troubleshooting and Understanding Error Messages

If you do not have your system configured properly, you may encounter certain error messages when trying to mount or access certain drives. Here are some of the more common error messages and their causes:

"mount: /dev/fd0 is not a valid block device"— The most common cause for this error is that the drive (in this example, /dev/fd0, corresponding to the floppy drive) is empty.

"mount: only root can mount /dev/fda on /mnt/floppy"— You do not have permission to mount this drive. Contact the system administrator, who can give you permission.

Note for System Administrators

	Note for System Administrators
	You can set a drive to be mountable and unmountable by users by adding "users" to the mount options (fourth column) in `/etc/fstab`. This may be done by hand or by using `linuxconf`, using the `Local volume` tab in Config->Filesystems->Access local drive. After you select the correct drive from the list, it will show you the `Volume specifications`. Click on the `Options` tab, and select the User mountable button.

You can set a drive to be mountable and unmountable by users by adding "users" to the mount options (fourth column) in /etc/fstab. This may be done by hand or by using linuxconf, using the Local volume tab in Config->Filesystems->Access local drive. After you select the correct drive from the list, it will show you the Volume specifications. Click on the Options tab, and select the User mountable button.

"mount: wrong fs type, bad option, bad superblock on /dev/cdrom, or too many mounted file systems"— This error can be caused by several problems. It is most commonly caused by not having the right filesystem type, such as trying to mount a music CDROM as if it held data, or trying to mount an msdos formatted floppy as ext2.
"mount /mnt/cdrom 2>&1 reported: mount: No medium found"— This error indicates the drive, in this case the CDROM drive, is empty.
"umount /mnt/cdrom 2>&1 reported: umount: /mnt/cdrom: device is busy"— This error indicates that the drive cannot be unmounted because the drive is being used by the computer. This often happens if you have the GNOME File Manager open to a directory on the drive or if you have a terminal window open with the working directory on the drive.

"umount: can't find /mnt/floppy in /etc/fstab or /etc/mtab "— This indicates that the system has not been configured to mount the mount point you are trying to use. In many cases, you may have put the wrong mount point in the Mount point entry in the Properties Dialog (see the section called Customization). To find out which mount point you should be using, contact your system administrator.

	Note for Advanced Users
	Each device (filesystem or drive) which can be mounted should be listed in the `/etc/fstab` configuration file. Reading this file will tell you which devices are configured for your system. To add or modify entries, you can edit this file by hand or by using the `linuxconf` application.

"mount: /dev/fd0 already mounted or /mnt/floppy busy mount: according to mtab, /dev/fd0 is mounted on /mnt/floppy_ext2 "— This error occurs if you have a single device (in this case /dev/fd0) configured for multiple mount points and you try to mount one mount point while another one is already mounted. Having multiple mount points for a single device typically is not necessary.
"mount: the kernel does not recognize /dev/sda4 as a block device(maybe 'insmod driver'?)"— Contact your system administrator. (This error occurs if your kernel is not properly configured to automatically mount the necessary kernel modules to read the device.)

Known Bugs and Limitations

Eject does not always work. Trying to eject with the drive mounted does not give a warning, explaining why the drive does not eject.

Authors

Drive Mount Applet was written by John Ellis (<johne@bellatlantic.net>). Please send all comments, suggestions, and bug reports to the GNOME bug tracking database. (Instructions for submitting bug reports can be found on-line. If you are using GNOME 1.1 or later, you can also use Bug Report Tool (bug-buddy), available in the Utilities submenu of Main Menu, for submitting bug reports.

This manual was written by Dan Mueth (<d-mueth@uchicago.edu>). Please send all comments and suggestions regarding this manual to the GNOME Documentation Project by sending an email to <docs@gnome.org>. You can also submit comments online by using the GNOME Documentation Status Table.

License

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

A copy of the GNU General Public License is included as an appendix to the GNOME Users Guide. You may also obtain a copy of the GNU General Public License from the Free Software Foundation by visiting their Web site or by writing to

     Free Software Foundation, Inc.
     59 Temple Place - Suite 330
     Boston, MA 02111-1307
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