Iomega Zip 100 USB Howto

For Red Hat Linux 7.2

By Phil Jones (pjls16812 at blueyonder.co.uk), August 2002

About this document

This page describes how I successfully got an Iomega Zip 100 USB removable storage disk drive working with Red Hat Linux 7.2.

The good news

Red Hat Linux 7.2 comes with all the necessary software to get your Iomega Zip 100 USB drive working.

How it works

The Zip drive is detected by the Linux Universal Serial Bus (USB) Universal Host Controller Interface (UHCI) during bootup. The drive is treated as a SCSI disk drive. If there are no other SCSI disk drives, the Zip drive becomes the device /dev/sda. An entry in the filesystems control file /dev/fstab is made automatically when the Zip drive is detected.

Preformatted Iomega 100 Mb Zip disks come with a single partition on them, either partition 1 or 4. So the Zip disk is accessible as the device /dev/sda1 or /dev/sda4, depending on how the Zip disk is partitioned. If the Zip disk isn't partitioned, or wants re-partitioning, we can partition it ourselves, and that is covered later in this howto.

Getting started

Turn off your computer. Plug in your Iomega Zip drive to your USB port and the mains power supply. Turn on. The Zip drive should be mentioned in the kernel messages that scroll up the screen as your system boots. Once your system is started, start a terminal and enter this command to review the kernel bootup messages: 

  dmesg

You should see lines like this: 

usb-uhci.c: v1.251:USB Universal Host Controller Interface driver
SCSI subsystem driver Revision: 1.00
Initializing USB Mass Storage driver...
usb.c: registered new driver usb-storage
usb-uhci.c: interrupt, status 2, frame# 1355
usb-uhci.c: interrupt, status 3, frame# 1356
scsi0 : SCSI emulation for USB Mass Storage devices
usb-uhci.c: interrupt, status 3, frame# 1363
  Vendor: IOMEGA    Model: ZIP 100           Rev: 11.V
  Type:   Direct-Access                      ANSI SCSI revision: 02
WARNING: USB Mass Storage data integrity not assured
USB Mass Storage device found at 2
USB Mass Storage support registered.

These lines tell you that the Zip drive has been recognised by the USB subsystem. Later on in the kernel messages, next to the messages about your hard disk and CD drives, you should see lines like this: 

Attached scsi removable disk sda at scsi0, channel 0, id 0, lun 0
SCSI device sda: 196608 512-byte hdwr sectors (101 MB)
sda: Write Protect is off
 sda: unknown partition table

These lines are about whatever disk might be in your Zip drive. It says the Zip drive is represented by the device file /dev/sda, and the disk isn't formatted because it has an unknown partition table. If your disk is formatted, the last line in the snippet above might be different.

Examining the disk partitions

Become root and enter this command. I assume your Zip drive is /dev/sda, if you have other SCSI disks, be careful! 

  fdisk /dev/sda

To view the partitions on the disk, press P. You might get results like this: 

Device     Boot   Start    End    Blocks   Id   System
/dev/sda4         1        1024   98280    b    Win95 FAT32

If your disk is partitioned like this, press Q to exit. If you need to create partitions, note that Zip disks usually contain a single partition, number 4 in the partition table on the Zip disk, of a Windows type.

Formatting the disk

To format the disk in Windows format, use this command: 

  mkfs.vfat /dev/sda4

Mounting the disk manually

To mount the disk manually, you would use a command like this: 

  mount -t vfat /dev/sda4 /mnt/zip100.0

Note that the last parameter refers to a directory created automatically when the Zip drive is detected.

Auto-mounting

To have the disk mounted on demand, a line like this is put in /etc/fstab automatically. Here it is: 

  /dev/sda4   /mnt/zip100.0   auto   noauto,owner,kudzu  0 0

This means the fourth partition on /dev/sda will be mounted to /mnt/zip100.0. The filesystem type will be determined automatically. The 'noauto' option means mount on demand. The 'owner' option means only the owner of the device file /dev/sda4 can mount the disk. The 'kudzu' option means the device can be controlled by Red Hat's 'kudzu' hardware manager. The last two options mean no dumping or checking at bootup apply to the Zip disk.

Quick help

I get the error "/dev/sda4 is not a valid block device"

Meaning: The Zip disk is not partitioned, there is no partition number 4 on the Zip disk, or partition number 4 on the Zip disk is not formatted.
Solution: Use fdisk /dev/sda to create partition number 4 if necessary. Then use mkfs to format the partition.