## Accessing disks and partitions

### CONTENTS

      1. Mounting devices
      2. Mounting devices with VASM
      3. The fstab file
      4. mount and umount commands

### 1. Mounting Devices

In Linux, all of the drives, partitions and devices in your computer are treated as "files". Various hard drive partitions, CD-ROMs, and floppies are all placed in the same filesystem tree. In order to be able to access the contents of those devices, external or internal devices, they must be "mounted".

The default installation of VectorLinux v6.0 enables the HAL automounting system. HAL detects newly attached devices such as USB devices, floppy disk , CD-DVD disks, etc. It then automounts them and then launches an appropriate application. It does this seamlessly in KDE and in xfce. In other window managers provided with VL 6.0 you will need to open the PCManFM file manager and check its right hand panel for your device and double click that device to get access to it. vl-hot is similar to HAL, but uses the udev system and is much less resource intensive. It would be more appropriate to use in a lower resource older computer, and especially with the VectorLinux Light Edition. At present though, vl-hot only works with JWM and IceWM as long as the PCManFM file manager is also installed (this is the case with VL Light 6.0).

With either HAL or vl-hot working properly inserting external devices such as any USB device, a floppy disk or a CD-DVD platter will cause them to be automounted and an appropriate application will launch or a new icon for accessing the device will appear on your desktop. However, if you use a desktop other than those listed in the paragraph above, add a new hard drive or want a device to be automounted whenever you reboot the computer then you will need to familiarize yourself with the Linux "mount" and "umount" commands and also learn about the mount configuration file: /etc/fstab. The rest of this document explains these concepts. Newbies probably do not need to concern themselves yet with these concepts.

The easiest way to mount a device such as a second hard disk or partition is by adding a permanent entry in the /etc/fstab file. In this manner the device will be automatically mounted for you at every boot.

Note:If you are not using HAL or vl-hot and you therefore do not know what device name has been assigned to the USB device you have just inserted then the easiest way to determine the device name is to open a terminal immediately after you have inserted the device and type "tail -f /var/log/messages". The second or third last line of the file should tell you the device name.

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### 2. Mounting devices with VASM

VASM provides an easy method to configure additional local disks or partitions to be mounted in your system. Just launch it, select "FILESYSTEM", then "MOUNT", and there you can ADD or REMOVE mount points.

- Adding mount points

> If you select "Add" you will be presented with a list of the local filesystems which are available and which are not already present in the fstab file (the file where mount points configuration is stored).

> Select the one you want to configure and you will be asked where you want it to be mounted. Then you will see the default options it will be mounted with. If you know what you are doing, you can modify these options, otherwise accept the defaults and press "Ok".

> The filesystem will not be automatically mounted, you will have to mount it manually by either command line, Kwikdisk, or utilities such as gkrellm.

> If you mount it by command line, and assuming you created a mount point in /mnt/win, you could use this command (as root):

> `mount /mnt/win`

> You could also use:

> `mount -a`

> this will mount all of the mount points available in the configuration file, /etc/fstab.

> Note: Keep in mind that the default settings make the filesystem mountable ONLY by the root user and not by ordinary users. If you want to make it mountable by users you could append "users," to the default options that are presented during the process.

- Deleting mount points

> When you delete a mount point, all you are doing is telling the system not to access some particular filesystem (disk, partition, etc,), you are not actually deleting any contents of that filesystem.

> So, if you choose to Delete a mount point, you will see a list of the devices configured to be mountable (not necessarily auto-mounted). Simply select those you want to remove and press "Ok". Their entries will be removed from the configuration files and nothing will be modified in the filesystem itself.

> Notes: It is highly recommended that you unmount the filesystem BEFORE you delete it's mount point. If you do not unmount the filesystem before, it will not be unmounted automatically, so you will have to do it either by command line, Kwikdisk, gkrellm or by rebooting the system.

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### 3. The fstab file

Since VL5, using VASM is all you need to know to mount your partitions or hardisks. However, for those wanting to know more about mounting devices, here is some additional information.

Let's look at an example of the /etc/fstab file:

| <device> | <mount point> | <type> | <options>
| /dev/hda3 | / | ext3 | defaults 1 1
| /dev/hda2 | swap | swap | defaults 0 0
| /dev/hda1 | /mnt/windows | vfat | defaults,noauto 0 0
| /dev/hda4 | /mnt/personal | vfat | defaults,auto,umask=000 0 0
| none none | /dev/pts /proc | devpts defaults | gid=5,mode=620 0 0 0 0
| /dev/fd0 | /mnt/floppy | msdos | defaults 0 0
| dev/cdrom | /mnt/cdrom | iso9660 | ro 0 0

The first column is the device name. In this case, the devices are four partitions in an IDE hard drive, two special filesystems that don't need a device, a floppy, and a CD-ROM drive. The second column is where in the directory tree the device will be mounted. This needs to be a directory name, except in the case of a swap partition. The third column is the filesystem type of the device. For Windows 9x filesystems, this will be vfat, for normal Linux filesystems, this will be ext2 (second extended filesystem). CD-ROM drives are iso9660, and other Windows-based devices will either be msdos or vfat. NTFS filesystems read support is available but write support is not fully reliable yet.

The umask section deals with access permissions to FAT devices. This is a very complex topic that goes beyond the scope of this guide, but keep in mind that the 000 option poses almost no restrictions about how regular users can access the device.

The last column is a listing of options that apply to the mounted filesystem. “defaults” is fine for just about everything. However, read-only devices should be given the ro flag. There are a lot of options that can be used. Check the fstab(5) man page for more information. The last two columns are used by fsck and other commands that need to manipulate the devices. Check the man page for that information, as well.

When you install VectorLinux, the setup program will build much of the fstab file. The only time you will need to edit it is if you add disks or want devices to be automatically mounted at boot time.

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### 4. mount and umount commands

Attaching another device to your filesystem is easy. All you have to do is use the mount command, along with a few options. Using mount can also be made much more simple if the device has an entry in the /etc/fstab file. For example, let's say that I wanted to mount my CD-ROM drive and that my fstab file looked like the example from the previous section. I would call mount like so:

`# mount /mnt/cdrom`

Since there is an entry in fstab for that mount point, mount knows what options to use. If there wasn't an entry for that device, I would have to use several options for mount:

`# mount -t iso9660 -o ro /dev/cdrom/cdrom`

That command line includes the same information as the example fstab did, but we'll go over all the parts anyways. The -t iso9660 is the filesystem type of the device to mount. In this case, it would be the iso9660 filesystem which is what CD-ROM drives most commonly use. The -o ro tells mount to mount the device read-only. The /dev/cdrom is the name of the device to mount, and /mnt/cdrom is the location on the filesystem to mount the drive.

Before you can remove a floppy, CD-ROM, or other removable device that is currently mounted, you'll have to unmount it. That is done using the `umount` command. You can use either the mounted device or the mount point as the argument to umount. For example, if you wanted to unmount the CD-ROM from the previous example, either of these commands would work:

`# umount /dev/cdrom
# umount /mnt/cdrom`

In the default configuration of VectorLinux, only the root user is able to mount and umount devices. You can allow regular users the ability to mount devices by adding "users" (without quotes) in your fstab file:

| /dev/hda4 | /mnt/personal | vfat | defaults,auto,users,umask=000 0 0

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