# Knowing Knoppix/Using an external USB drive

Knoppix supports two types of external USB hard drive:
* USB hard drive stick (flash drive or pen drive).
* Conventional external USB hard disk drive.
Knoppix uses its built-in USB Mass Storage driver to support these drives. Both USB 1.1 and the faster USB 2.0 drives are supported. USB 1.1 drives work at 12 Mbits per second (about 1.5 megabytes per second). USB 2.0 drives work at up to 480 Mbits per second (about 60 megabytes per second) when plugged into a USB 2.0 capable socket.
A USB hard drive stick is a small device like a key fob. Many digital cameras also work as an external USB hard drive. Any digital camera will work provided it supports USB Mass Storage. Some digital cameras have to be put in “DSC Mode” to enable USB Mass Storage. To copy files onto an external USB hard disk drive:
* Insert the USB drive into any USB socket.
* After a short pause, an icon for each partition on the new drive should appear. In most cases there will be a single partition on the USB drive that covers the entire disk, so one new icon will appear. If the icon doesn't appear, take the USB drive out and insert it again more slowly. There are four pins on the USB drive's connector. Two of the four pins are longer because they must make contact first. To see if Knoppix accepts the USB drive when you put it in, refer to the “Identifying Hardware” section. Look at the Info Center's “USB Devices” and “Storage Devices” categories.
* When USB drive icon appears, click it with the left mouse button.
* Wait for a moment while it is mounted.
* The files on the USB drive will be displayed.
* Right-click the icon of the USB drive.
* Click “Change read-write mode”.
* Click “Yes”.
* Drag and drop the files or folders that you want to copy into the window of the USB drive.
* Click “Copy Here”.
* The files or folders will be copied.
* When copying has finished, close all open windows for the USB drive.
* Right-click on the icon of the USB drive.
* Click “Unmount”.
* The green triangle on the USB drive's icon will go away.
* It is now safe to take the USB drive out of its socket.

## Quick help

Question: I still can't get my USB drive to appear. Click Konsole, then type dmesg. If the drive is connected successfully, you will see lines like this at or near the end of the output:
This shows that a “USB2.0 Flash Disk” has appeared as the first SCSI drive (sda). It is 262 Mb in size. It contains one partition (sda1). If you insert a USB drive too quickly, it will say “unable to read partition table” instead of “SCSI device”. This means try again, more slowly.
If it still won't work, try using another USB socket.
Or you may try mounting the drive by hand:
Note:If the 'usbdisk' mount point doesn't exist, use an unused existing mount or create the mount point yourself
If that doesn't help, try starting Knoppix with the USB drive already connected. If it really won't work, buy or borrow a USB hub PCI expansion card. Put it into the computer and try connecting the USB drive to the expansion card, rather than to the computer's built-in USB ports.
Question: Why did it say “out of disk space” when copying to the flash drive, even though the total size of the files to be copied is less than the free space on the drive? Some flash drives are formatted with the FAT12 or FAT16 filesystem. This is inefficient when storing small files. If there are a lot of small files, the flash drive may fill up much more quickly that you might expect. There are two ways round the problem. The first way is to archive the files onto the flash drive. To archive means to create one big file instead of lots of small ones. To create an archive, click K menu, Utilities, Ark (Archiving Tool). The second way is to reformat the drive to a more efficient filesystem, such as FAT32.